vpruthi/doc-exports
1
0
Fork 0
forked from docs/doc-exports
Code Pull Requests Activity

DCS UMN 20230208 version

Browse Source 
Reviewed-by: Mützel, Andrea <andrea.muetzel@t-systems.com>
Co-authored-by: Chen, Junjie <chenjunjie@huawei.com>
Co-committed-by: Chen, Junjie <chenjunjie@huawei.com>
This commit is contained in:
Chen, Junjie 2023-06-23 13:27:54 +00:00 committed by zuul
parent a7882cf1e5
commit 3b672beb23
165 changed files with 4771 additions and 2455 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

0
docs/dcs/umn/.placeholder
View File

676
docs/dcs/umn/ALL_META.TXT.json
View File

File diff suppressed because it is too large Load Diff

894
docs/dcs/umn/CLASS.TXT.json
View File

File diff suppressed because it is too large Load Diff

6
docs/dcs/umn/CacheCluster.html
View File

@ -1,9 +1,9 @@
<a name="CacheCluster"></a><a name="CacheCluster"></a>
<h1 class="topictitle1">Proxy Cluster Redis</h1>
<div id="body1600250975360"><p id="CacheCluster__p16121033102019">DCS provides two types of cluster Redis instances: Proxy Cluster and Redis Cluster. Proxy Cluster uses Linux Virtual Server (LVS) and proxies. Redis Cluster is the native distributed implementation of Redis. Proxy Cluster instances are compatible with Redis 3.0, while Redis Cluster instances are compatible with Redis 4.0 and 5.0.</p>
<p id="CacheCluster__p13103105219146">This section describes Proxy Cluster DCS Redis 3.0 instances.</p>
<div class="note" id="CacheCluster__note134811721192210"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="CacheCluster__ul1758133822318"><li id="CacheCluster__li758133852319">A Proxy Cluster instance can be connected in the same way that a single-node or master/standby instance is connected, without any special settings on the client. You can use the IP address or domain name of the instance, and do not need to know or use the proxy or shard addresses.</li></ul>
<div id="body1600250975360"><p id="CacheCluster__p1691110491160">DCS for Redis provides Proxy Cluster instances, which use Linux Virtual Server (LVS) and proxies to achieve high availability.</p>
<p id="CacheCluster__p13103105219146">Proxy Cluster DCS Redis instances are compatible with Redis 3.0.</p>
<div class="note" id="CacheCluster__note134811721192210"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="CacheCluster__ul1758133822318"><li id="CacheCluster__li758133852319">A Proxy Cluster instance can be connected in the same way that a single-node or master/standby instance is connected, without any special settings on the client. You can use the IP address of the instance, and do not need to know or use the proxy or shard addresses.</li></ul>
</div></div>
<div class="section" id="CacheCluster__section861823615325"><h4 class="sectiontitle">Proxy Cluster DCS Redis 3.0 Instances</h4><p id="CacheCluster__p10878151913448">Proxy Cluster DCS Redis 3.0 instances are compatible with <a href="https://github.com/CodisLabs/codis" target="_blank" rel="noopener noreferrer">codis</a>. The specifications range from 64 GB to 1024 GB, meeting requirements for <strong id="CacheCluster__b13211893475612">millions of concurrent connections</strong> and <strong id="CacheCluster__b45541541375612">massive data cache</strong>. Distributed data storage and access is implemented by DCS, without requiring development or maintenance.</p>
<p id="CacheCluster__p186619405101">Each Proxy Cluster instance consists of load balancers, proxies, cluster managers, and <a href="dcs-pd-200312004.html#dcs-pd-200312004__en-us_topic_0145956240_section20999323134412">shards</a>.</p>

20
docs/dcs/umn/CacheMasterSlave.html
View File

@ -1,8 +1,8 @@
<a name="CacheMasterSlave"></a><a name="CacheMasterSlave"></a>
<h1 class="topictitle1">Master/Standby Redis</h1>
<div id="body1600250974776"><p id="CacheMasterSlave__p11826145419223">This section describes master/standby DCS Redis instances. Three Redis versions are available for master/standby DCS Redis instances: Redis 3.0, Redis 4.0, and Redis 5.0.</p>
<div class="note" id="CacheMasterSlave__note67021744211"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheMasterSlave__p157220441816">You cannot upgrade the Redis version for an instance. For example, a master/standby DCS Redis 3.0 instance cannot be upgraded to a master/standby DCS Redis 4.0 or 5.0 instance. If your service requires the features of higher Redis versions, create a DCS Redis instance of a higher version and then migrate data from the old instance to the new one.</p>
<div id="body1600250974776"><p id="CacheMasterSlave__p11826145419223">This section describes master/standby DCS Redis instances. Redis versions available for master/standby DCS Redis instances include Redis 3.0, 4.0, 5.0, and 6.0.</p>
<div class="note" id="CacheMasterSlave__note67021744211"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheMasterSlave__p157220441816">You cannot upgrade the Redis version for an instance. For example, a master/standby DCS Redis 4.0 instance cannot be upgraded to a master/standby DCS Redis 5.0 instance. If your service requires the features of higher Redis versions, create a DCS Redis instance of a higher version and then migrate data from the old instance to the new one.</p>
</div></div>
<div class="section" id="CacheMasterSlave__section2115135632817"><h4 class="sectiontitle">Features</h4><p id="CacheMasterSlave__p29361111432">Master/Standby DCS instances have higher availability and reliability than single-node DCS instances.</p>
<p id="CacheMasterSlave__p152081045174518">Master/Standby DCS instances have the following features:</p>
@ -11,13 +11,11 @@
</li><li id="CacheMasterSlave__li10688192120301"><strong id="CacheMasterSlave__b6852014317">Data synchronization</strong><p id="CacheMasterSlave__p2581425163010">Data in the master and standby nodes is kept consistent through incremental synchronization.</p>
<div class="note" id="CacheMasterSlave__note1745795093018"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheMasterSlave__p6458135018301">After recovering from a network exception or node fault, master/standby instances perform a full synchronization to ensure data consistency.</p>
</div></div>
</li><li id="CacheMasterSlave__li142654132115"><strong id="CacheMasterSlave__b117861923114313">Automatic master/standby switchover</strong><p id="CacheMasterSlave__p1922564615389">If the master node becomes faulty, the standby node takes over within 30 seconds, without requiring any service interruptions or manual operations.</p>
</li><li id="CacheMasterSlave__li426374543318"><strong id="CacheMasterSlave__b415742710491">DR policies</strong><p id="CacheMasterSlave__p13889754193315">Each master/standby instance can be deployed across AZs with physically isolated power supplies and networks. Applications can also be deployed across AZs to achieve high availability for both data and applications.</p>
</li><li id="CacheMasterSlave__li142654132115"><strong id="CacheMasterSlave__b117861923114313">Automatic master/standby switchover</strong><p id="CacheMasterSlave__p1922564615389">If the master node becomes faulty, the instance is disconnected and unavailable for several seconds. The standby node takes over within 30 seconds without manual operations to resume stable services.</p>
</li><li id="CacheMasterSlave__li426374543318"><strong id="CacheMasterSlave__b415742710491">DR policies</strong><p id="CacheMasterSlave__p13889754193315">Each master/standby DCS instance can be deployed across AZs with physically isolated power supplies and networks. Applications can also be deployed across AZs to achieve high availability for both data and applications.</p>
</li></ol>
</div>
<div class="section" id="CacheMasterSlave__section1728321782810"><h4 class="sectiontitle">Architecture</h4><p id="CacheMasterSlave__p139021259112"><a href="#CacheMasterSlave__fig14477142816340">Figure 1</a> shows the architecture of master/standby DCS Redis instances.</p>
<div class="note" id="CacheMasterSlave__note12240134982910"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheMasterSlave__p11242249122915">To access a DCS Redis 3.0 instance, you must use port 6379. To access a DCS Redis 4.0 or 5.0 instance, you can customize the port. If no port is specified, the default port 6379 will be used. In the following architecture, port 6379 is used. If you have customized a port, replace <strong id="CacheMasterSlave__b185911833202410">6379</strong> with the actual port.</p>
</div></div>
<div class="section" id="CacheMasterSlave__section1728321782810"><h4 class="sectiontitle">Architecture of DCS Redis 3.0 Instances</h4><p id="CacheMasterSlave__p139021259112"><a href="#CacheMasterSlave__fig14477142816340">Figure 1</a> shows the architecture of master/standby DCS Redis instances.</p>
<div class="fignone" id="CacheMasterSlave__fig14477142816340"><a name="CacheMasterSlave__fig14477142816340"></a><a name="fig14477142816340"></a><span class="figcap"><b>Figure 1 </b>Master/Standby DCS instance architecture</span><br><span><img id="CacheMasterSlave__image1555620406535" src="en-us_image_0296786164.png"></span></div>
<p id="CacheMasterSlave__p153106583326">Architecture description:</p>
<ul id="CacheMasterSlave__ul1631417191120"><li id="CacheMasterSlave__li20179270479"><strong id="CacheMasterSlave__b264814218559">VPC</strong><p id="CacheMasterSlave__p89401530124718">All server nodes of the instance run in the same VPC.</p>
@ -28,9 +26,15 @@
<p id="CacheMasterSlave__p20951317243">DCS Redis instances are compatible with the Redis protocol, and can be accessed through open-source clients. For details about accessing DCS instances, see <a href="dcs-ug-0916002.html">Accessing an Instance</a>.</p>
</li><li id="CacheMasterSlave__li81722784711"><strong id="CacheMasterSlave__b18417232969">DCS instance</strong><p id="CacheMasterSlave__p141487982311">Indicates a master/standby DCS instance which has a master node and a standby node. By default, data persistence is enabled and data is synchronized between the two nodes.</p>
<p id="CacheMasterSlave__p1542317478287">DCS monitors the availability of the instance in real time. If the master node becomes faulty, the standby node becomes the master node and resumes service provisioning.</p>
<p id="CacheMasterSlave__p828195918488">DCS Redis instances are accessed through port 6379 by default.</p>
<p id="CacheMasterSlave__p828195918488">DCS Redis 3.0 instances are accessed through port 6379 by default. Port customization is not supported.</p>
</li></ul>
</div>
<div class="section" id="CacheMasterSlave__section5805185095215"><h4 class="sectiontitle">Architecture of Master/Standby DCS Redis 4.0/5.0/6.0 Instances </h4><p id="CacheMasterSlave__p9460152115104">The following figure shows the architecture of a master/standby DCS Redis 4.0/5.0/6.0 instance.</p>
<div class="fignone" id="CacheMasterSlave__fig16986121191016"><span class="figcap"><b>Figure 2 </b>Architecture of a master/standby DCS Redis 4.0/5.0/6.0 instance</span><br><span><img class="eddx" id="CacheMasterSlave__image1598717119108" src="en-us_image_0000001478356482.png"></span></div>
<p id="CacheMasterSlave__p08712785615">Architecture description:</p>
<ol id="CacheMasterSlave__ol1898612288020"><li id="CacheMasterSlave__li121237313010">Master/standby DCS Redis 4.0/5.0/6.0 instances support Sentinels. Sentinels monitor the running status of the master and standby nodes. If the master node becomes faulty, a failover will be performed.<p id="CacheMasterSlave__p137811591512"><a name="CacheMasterSlave__li121237313010"></a><a name="li121237313010"></a>Sentinels are invisible to you and is used only in the service. </p>
</li><li id="CacheMasterSlave__li18916171615119">A standby node has the same specifications as a master node. A master/standby instance consists of a pair of master and standby nodes by default.</li><li id="CacheMasterSlave__li1236204215435">To access a DCS Redis 4.0/5.0/6.0 instance, you can customize the port. If no port is specified, the default port 6379 will be used. In the architecture diagram, port 6379 is used. If you have customized a port, replace <strong id="CacheMasterSlave__b116713868943641">6379</strong> with the actual port.</li></ol>
</div>
</div>
<div>
<div class="familylinks">

55
docs/dcs/umn/CacheProxy.html
View File

@ -1,70 +1,71 @@
<a name="CacheProxy"></a><a name="CacheProxy"></a>
<h1 class="topictitle1">Redis Cluster</h1>
<div id="body1600250976541"><p id="CacheProxy__p7253192101916">This section describes Redis Cluster DCS Redis 4.0 and 5.0 instances.</p>
<div class="section" id="CacheProxy__section880163191618"><h4 class="sectiontitle">Redis Cluster DCS Redis 4.0 and 5.0 Instances</h4><p id="CacheProxy__p1977021012338">The Redis Cluster instance type provided by DCS is compatible with the <a href="https://redis.io/topics/cluster-spec" target="_blank" rel="noopener noreferrer">native Redis Cluster</a>, which uses smart clients and a distributed architecture to perform sharding.</p>
<div id="body1600250976541"><p id="CacheProxy__p4126104312716">Redis Cluster DCS instances use the native distributed implementation of Redis.</p>
<p id="CacheProxy__p7253192101916">Redis Cluster DCS instances are compatible with Redis 4.0 and 5.0.</p>
<div class="section" id="CacheProxy__section880163191618"><h4 class="sectiontitle">Redis Cluster</h4><p id="CacheProxy__p1977021012338">The Redis Cluster instance type provided by DCS is compatible with the <a href="https://redis.io/topics/cluster-spec" target="_blank" rel="noopener noreferrer">native Redis Cluster</a>, which uses smart clients and a distributed architecture to perform sharding.</p>
<p id="CacheProxy__p164954315218"><a href="#CacheProxy__table3552324111">Table 1</a> lists the shard specification for different instance specifications.</p>
<p id="CacheProxy__p17223016111"><strong id="CacheProxy__b94915132075659">Specification per shard=Instance specification/Number of shards</strong>. For example, if a 48 GB instance has 6 shards, the specification of each shard is 48 GB/6 = 8 GB.</p>
<p id="CacheProxy__p17223016111"><strong id="CacheProxy__b846424631919">Size of a shard = Instance specification/Number of shards</strong>. For example, if a 48 GB instance has 6 shards, the size of each shard is 48 GB/6 = 8 GB.</p>
<div class="tablenoborder"><a name="CacheProxy__table3552324111"></a><a name="table3552324111"></a><table cellpadding="4" cellspacing="0" summary="" id="CacheProxy__table3552324111" frame="border" border="1" rules="all"><caption><b>Table 1 </b>Specifications of Redis Cluster DCS instances</caption><thead align="left"><tr id="CacheProxy__row65521623113"><th align="left" class="cellrowborder" valign="top" width="44.12%" id="mcps1.3.2.5.2.3.1.1"><p id="CacheProxy__p1955210211118">Total Memory</p>
<div class="tablenoborder"><a name="CacheProxy__table3552324111"></a><a name="table3552324111"></a><table cellpadding="4" cellspacing="0" summary="" id="CacheProxy__table3552324111" frame="border" border="1" rules="all"><caption><b>Table 1 </b>Specifications of Redis Cluster DCS instances</caption><thead align="left"><tr id="CacheProxy__row65521623113"><th align="left" class="cellrowborder" valign="top" width="44.12%" id="mcps1.3.3.5.2.3.1.1"><p id="CacheProxy__p1955210211118">Total Memory</p>
</th>
<th align="left" class="cellrowborder" valign="top" width="55.879999999999995%" id="mcps1.3.2.5.2.3.1.2"><p id="CacheProxy__p04843421456">Shards</p>
<th align="left" class="cellrowborder" valign="top" width="55.879999999999995%" id="mcps1.3.3.5.2.3.1.2"><p id="CacheProxy__p04843421456">Shards</p>
</th>
</tr>
</thead>
<tbody><tr id="CacheProxy__row155314218115"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p491514405611">4 GB/8 GB/16 GB/24 GB/32 GB</p>
<tbody><tr id="CacheProxy__row155314218115"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p491514405611">4 GB/8 GB/16 GB/24 GB/32 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p207903579620">3</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p207903579620">3</p>
</td>
</tr>
<tr id="CacheProxy__row1731117227614"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p99166401567">48 GB</p>
<tr id="CacheProxy__row1731117227614"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p99166401567">48 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p1779095710616">6</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p1779095710616">6</p>
</td>
</tr>
<tr id="CacheProxy__row113126221669"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p891617401862">64 GB</p>
<tr id="CacheProxy__row113126221669"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p891617401862">64 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p97906571561">8</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p97906571561">8</p>
</td>
</tr>
<tr id="CacheProxy__row10313162217619"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p19161140362">96 GB</p>
<tr id="CacheProxy__row10313162217619"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p19161140362">96 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p879011574611">12</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p879011574611">12</p>
</td>
</tr>
<tr id="CacheProxy__row93136221568"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p15916164015619">128 GB</p>
<tr id="CacheProxy__row93136221568"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p15916164015619">128 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p1679065712610">16</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p1679065712610">16</p>
</td>
</tr>
<tr id="CacheProxy__row123147221965"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p1591613409619">192 GB</p>
<tr id="CacheProxy__row123147221965"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p1591613409619">192 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p137910577616">24</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p137910577616">24</p>
</td>
</tr>
<tr id="CacheProxy__row1297218281269"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p4916140966">256 GB</p>
<tr id="CacheProxy__row1297218281269"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p4916140966">256 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p87911957860">32</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p87911957860">32</p>
</td>
</tr>
<tr id="CacheProxy__row14566154853519"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p356774883515">384 GB</p>
<tr id="CacheProxy__row14566154853519"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p356774883515">384 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p10567548133513">48</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p10567548133513">48</p>
</td>
</tr>
<tr id="CacheProxy__row8567124814359"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p14311185913513">512 GB</p>
<tr id="CacheProxy__row8567124814359"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p14311185913513">512 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p20567184883518">64</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p20567184883518">64</p>
</td>
</tr>
<tr id="CacheProxy__row7567114814356"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p967654163618">768 GB</p>
<tr id="CacheProxy__row7567114814356"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p967654163618">768 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p13568194813354">96</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p13568194813354">96</p>
</td>
</tr>
<tr id="CacheProxy__row1656844810350"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.2.5.2.3.1.1 "><p id="CacheProxy__p209424813617">1024 GB</p>
<tr id="CacheProxy__row1656844810350"><td class="cellrowborder" valign="top" width="44.12%" headers="mcps1.3.3.5.2.3.1.1 "><p id="CacheProxy__p209424813617">1024 GB</p>
</td>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.2.5.2.3.1.2 "><p id="CacheProxy__p155682483350">128</p>
<td class="cellrowborder" valign="top" width="55.879999999999995%" headers="mcps1.3.3.5.2.3.1.2 "><p id="CacheProxy__p155682483350">128</p>
</td>
</tr>
</tbody>

8
docs/dcs/umn/CacheSingleNode.html
View File

@ -1,7 +1,9 @@
<a name="CacheSingleNode"></a><a name="CacheSingleNode"></a>
<h1 class="topictitle1">Single-Node Redis</h1>
<div id="body1600250973735"><p id="CacheSingleNode__p138101212403">Three Redis versions are available for single-node DCS Redis instances: Redis 3.0, Redis 4.0, and Redis 5.0.</p>
<div id="body1600250973735"><p id="CacheSingleNode__p11541643103710">Single-node DCS Redis instances are available in versions 3.0/4.0/5.0/6.0.</p>
<div class="note" id="CacheSingleNode__note5258316142416"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheSingleNode__p11302105411119">You cannot upgrade the Redis version for an instance. For example, a single-node DCS Redis 4.0 instance cannot be upgraded to a single-node DCS Redis 5.0 instance. If your service requires the features of higher Redis versions, create a DCS Redis instance of a higher version and then migrate data from the old instance to the new one.</p>
</div></div>
<div class="section" id="CacheSingleNode__section19260552619"><h4 class="sectiontitle">Features</h4><ol id="CacheSingleNode__ol67507623011"><li id="CacheSingleNode__li107501061301">Low system overhead and high QPS<p id="CacheSingleNode__p22461983014"><a name="CacheSingleNode__li107501061301"></a><a name="li107501061301"></a>Single-node instances do not support data synchronization or data persistence, reducing system overhead and supporting higher concurrency. QPS of single-node DCS Redis instances reaches up to 100,000.</p>
</li><li id="CacheSingleNode__li77501762306">Process monitoring and automatic fault recovery<p id="CacheSingleNode__p1917103533114"><a name="CacheSingleNode__li77501762306"></a><a name="li77501762306"></a>With an HA monitoring mechanism, if a single-node DCS instance becomes faulty, a new process is started within 30 seconds to resume service provisioning.</p>
</li><li id="CacheSingleNode__li975015614309">Out-of-the-box usability and no data persistence<p id="CacheSingleNode__p667242253214"><a name="CacheSingleNode__li975015614309"></a><a name="li975015614309"></a>Single-node DCS instances can be used out of the box because they do not involve data loading. If your service requires high QPS, you can warm up the data beforehand to avoid strong concurrency impact on the backend database.</p>
@ -10,12 +12,12 @@
<p id="CacheSingleNode__p188211915114319">In summary, single-node DCS instances support highly concurrent read/write operations, but do not support data persistence. Data will be deleted after instances are restarted. They are suitable for scenarios which do not require data persistence, such as database front-end caching, to accelerate access and ease the concurrency load off the backend. If the desired data does not exist in the cache, requests will go to the database. When restarting the service or the DCS instance, you can pre-generate cache data from the disk database to relieve pressure on the backend during startup.</p>
</div>
<div class="section" id="CacheSingleNode__section350919180019"><h4 class="sectiontitle">Architecture</h4><p id="CacheSingleNode__p169821159154813"><a href="#CacheSingleNode__fig15457185394718">Figure 1</a> shows the architecture of single-node DCS Redis instances.</p>
<div class="note" id="CacheSingleNode__note12240134982910"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheSingleNode__p11242249122915">To access a DCS Redis 3.0 instance, you must use port 6379. To access a DCS Redis 4.0 or 5.0 instance, you can customize the port. If no port is specified, the default port 6379 will be used. In the following architecture, port 6379 is used. If you have customized a port, replace <strong id="CacheSingleNode__b1442135013241">6379</strong> with the actual port.</p>
<div class="note" id="CacheSingleNode__note12240134982910"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheSingleNode__p11242249122915">To access a DCS Redis 3.0 instance, you must use port 6379. To access a DCS Redis 4.0/5.0/6.0 instance, you can customize the port. If no port is specified, the default port 6379 will be used. In the following architecture, port 6379 is used. If you have customized a port, replace <strong id="CacheSingleNode__b1442135013241">6379</strong> with the actual port.</p>
</div></div>
<div class="fignone" id="CacheSingleNode__fig15457185394718"><a name="CacheSingleNode__fig15457185394718"></a><a name="fig15457185394718"></a><span class="figcap"><b>Figure 1 </b>Single-node DCS Redis instance architecture</span><br><span><img id="CacheSingleNode__image9134201365216" src="en-us_image_0296784660.png"></span></div>
<p id="CacheSingleNode__p153106583326">Architecture description:</p>
<ul id="CacheSingleNode__ul1631417191120"><li id="CacheSingleNode__li20179270479"><strong id="CacheSingleNode__b264814218559">VPC</strong><p id="CacheSingleNode__p89401530124718">All server nodes of the instance run in the same VPC.</p>
<div class="note" id="CacheSingleNode__note04501339113"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheSingleNode__p124516392019">For intra-VPC access, the client and the instance must be in the same VPC with specified security group rule configurations with specified security group rule configurations.</p>
<div class="note" id="CacheSingleNode__note04501339113"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="CacheSingleNode__p124516392019">For intra-VPC access, the client and the instance must be in the same VPC with specified security group rule configurations.</p>
<p id="CacheSingleNode__p14803202620398">For details, see <a href="en-us_topic_0090662012.html">Security Group Configurations</a>.</p>
</div></div>
</li><li id="CacheSingleNode__li017927194718"><strong id="CacheSingleNode__b386793812488">Application</strong><p id="CacheSingleNode__p36064574817">The client of the instance, which is the application running on an Elastic Cloud Server (ECS).</p>

9
docs/dcs/umn/GlobalDRPolicy.html
View File

@ -1,10 +1,10 @@
<a name="GlobalDRPolicy"></a><a name="GlobalDRPolicy"></a>
<h1 class="topictitle1">HA and DR Policies</h1>
<h1 class="topictitle1">Disaster Recovery and Multi-Active Solution</h1>
<div id="body8662426"><p id="GlobalDRPolicy__en-us_topic_0161126124_p8060118">Whether you use DCS as the frontend cache or backend data store, DCS is always ready to ensure data reliability and service availability. The following figure shows the evolution of DCS DR architectures.</p>
<div class="fignone" id="GlobalDRPolicy__en-us_topic_0161126124_fig16302053154911"><span class="figcap"><b>Figure 1 </b>DCS DR architecture evolution</span><br><span><img id="GlobalDRPolicy__en-us_topic_0161126124_image153322437119" src="en-us_image_0266235346.png"></span></div>
<p id="GlobalDRPolicy__en-us_topic_0161126124_p196901189533">To meet the reliability requirements of your data and services, you can choose to deploy your DCS instance within a single AZ or across AZs.</p>
<div class="section" id="GlobalDRPolicy__en-us_topic_0161126124_section9873193151517"><h4 class="sectiontitle">Single-AZ HA</h4><p id="GlobalDRPolicy__en-us_topic_0161126124_p11449191363119">Single-AZ deployment means deploying an instance within a physical equipment room. DCS provides process/service HA, data persistence, and hot standby DR policies for different types of DCS instances.</p>
<div class="section" id="GlobalDRPolicy__en-us_topic_0161126124_section9873193151517"><h4 class="sectiontitle">Single-AZ HA</h4><p id="GlobalDRPolicy__en-us_topic_0161126124_p11449191363119">Single-AZ deployment means to deploy an instance within a physical equipment room. DCS provides process/service HA, data persistence, and hot standby DR policies for different types of DCS instances.</p>
<p id="GlobalDRPolicy__en-us_topic_0161126124_p1795194162611"><strong id="GlobalDRPolicy__en-us_topic_0161126124_b67201447135919">Single-node DCS instance</strong>: When DCS detects a process fault, a new process is started to ensure service HA.</p>
<div class="fignone" id="GlobalDRPolicy__en-us_topic_0161126124_fig175040231000"><span class="figcap"><b>Figure 2 </b>HA for a single-node DCS instance deployed within an AZ</span><br><span><img class="vsd" id="GlobalDRPolicy__en-us_topic_0161126124_image164201427202219" src="en-us_image_0266235448.png"></span></div>
<p id="GlobalDRPolicy__en-us_topic_0161126124_p398014445284"><strong id="GlobalDRPolicy__en-us_topic_0161126124_b166451111105">Master/Standby DCS instance</strong>: Data is persisted to disk in the master node and incrementally synchronized and persisted to the standby node, achieving hot standby and data persistence.</p>
@ -16,8 +16,11 @@
<div class="fignone" id="GlobalDRPolicy__en-us_topic_0161126124_fig2046754742112"><span class="figcap"><b>Figure 5 </b>Cross-AZ deployment of a master/standby DCS instance</span><br><span><img class="vsd" id="GlobalDRPolicy__en-us_topic_0161126124_image1079294613241" src="en-us_image_0266235441.png"></span></div>
<div class="note" id="GlobalDRPolicy__en-us_topic_0161126124_note41824212218"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="GlobalDRPolicy__en-us_topic_0161126124_p17181423225">This mechanism applies in a similar way to a cluster DCS instance. Each shard (process) is deployed across AZs.</p>
</div></div>
<p id="GlobalDRPolicy__en-us_topic_0161126124_p1333015655118">When creating a master/standby or cluster DCS instance, select a standby AZ that is different from the primary AZ.</p>
<p id="GlobalDRPolicy__en-us_topic_0161126124_p1333015655118">When creating a master/standby or cluster DCS instance, select a standby AZ that is different from the primary AZ. See the following figure.</p>
<div class="fignone" id="GlobalDRPolicy__fig595045613515"><span class="figcap"><b>Figure 6 </b>Selecting different AZs</span><br><span><img id="GlobalDRPolicy__image149501556173516" src="en-us_image_0000001536314713.png"></span></div>
<p id="GlobalDRPolicy__p1110819147496">Backup, configuration modification, and password change functions cannot be used during the fault.</p>
<div class="note" id="GlobalDRPolicy__note58555412312"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="GlobalDRPolicy__p28555410310">You can deploy your application across AZs to ensure both data reliability and service availability in the event of power supply or network disruptions.</p>
</div></div>
</div>
</div>
<div>

84
docs/dcs/umn/RedisDifference.html
View File

File diff suppressed because it is too large Load Diff

2
docs/dcs/umn/dcs-faq-0220721.html
View File

@ -9,7 +9,7 @@
<ul id="dcs-faq-0220721__en-us_topic_0000001357973609_ul117685904813"><li id="dcs-faq-0220721__en-us_topic_0000001357973609_li517635914813">If flow control is always triggered when the bandwidth usage is low, there may be service microbursts or big or hot keys. In this case, check for big or hot keys.</li><li id="dcs-faq-0220721__en-us_topic_0000001357973609_li21761559164816">If the bandwidth usage remains high, the bandwidth limit may be exceeded. In this case, expand the capacity. Larger capacity supports higher bandwidth.</li></ul>
<p id="dcs-faq-0220721__en-us_topic_0000001357973609_p737634574812">For cluster instances:</p>
<ul id="dcs-faq-0220721__en-us_topic_0000001357973609_ul20813103175118"><li id="dcs-faq-0220721__en-us_topic_0000001357973609_li188139365110">If flow control is triggered only on one or a few shards, the shards may have big or hot keys.</li><li id="dcs-faq-0220721__en-us_topic_0000001357973609_li178131439513">If flow control or high bandwidth usage occurs on all or most shards at the same time, bandwidth usage of the instance has reached the limit. In this case, expand the instance capacity.</li></ul>
<div class="note" id="dcs-faq-0220721__en-us_topic_0000001357973609_note13959936343"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="dcs-faq-0220721__en-us_topic_0000001357973609_p16190307316">You can analyze big keys and hot keys on the DCS console. For details, see <a href="dcs-ug-190808001.html">Cache Analysis</a>.</p>
<div class="note" id="dcs-faq-0220721__en-us_topic_0000001357973609_note13959936343"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="dcs-faq-0220721__ul14277188191313"><li id="dcs-faq-0220721__li727719815135">You can analyze big keys and hot keys on the DCS console. For details, see <a href="dcs-ug-190808001.html">Analyzing Big Keys and Hot Keys</a>.</li><li id="dcs-faq-0220721__li142771789134">Running commands (such as <strong id="dcs-faq-0220721__b158183115314">KEYS</strong>) that consume lots of resources may cause high CPU and bandwidth usage. As a result, flow control is triggered.</li></ul>
</div></div>
</div>
<div>

2
docs/dcs/umn/dcs-faq-0326019.html
View File

@ -20,7 +20,7 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0326024.html">Data Backup, Export, and Migration</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-191204001.html">Master/Standby Switchover</a></strong><br>
</li>

10
docs/dcs/umn/dcs-faq-0326020.html
View File

@ -6,10 +6,12 @@
<ul class="ullinks">
<li class="ulchildlink"><strong><a href="en-us_topic_0090662012.html">Security Group Configurations</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730001.html">Does DCS Support Public Access?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0730001.html">Does DCS Support Access over Public Networks?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="en-us_topic_0100698850.html">Does DCS Support Cross-VPC Access?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0427005.html">Why Is "(error) NOAUTH Authentication required" Displayed When I Access a DCS Redis Instance?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730004.html">What Should I Do If Access to DCS Fails After Server Disconnects?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730005.html">Why Do Requests Sometimes Time Out in Clients?</a></strong><br>
@ -22,10 +24,14 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730009.html">What If "ERR Unsupported CONFIG subcommand" is Displayed in SpringCloud?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730010.html">How Do I Troubleshoot Redis Connection Failures?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0427015.html">Is a Password Required for Accessing an Instance? How Do I Set a Password?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730011.html">What Should Be Noted When Using Redis for Pub/Sub?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730010.html">How Do I Troubleshoot Redis Connection Failures?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-210721003.html">What Can I Do If Error "Cannot assign requested address" Is Returned When I Access Redis Using connect?</a></strong><br>
</li>
</ul>
<div class="familylinks">

8
docs/dcs/umn/dcs-faq-0326021.html
View File

@ -8,13 +8,13 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730013.html">Can I Change the VPC and Subnet for a DCS Redis Instance?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730014.html">Why Aren't Security Groups Configured for DCS Redis 4.0 and 5.0 Instances?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0730014.html">Why Aren't Security Groups Configured for DCS Redis 4.0/5.0/6.0 Instances?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730015.html">Do DCS Redis Instances Limit the Size of a Key or Value?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730017.html">Can I Obtain the Addresses of the Nodes in a Cluster DCS Redis Instance?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730018.html">Why Is Available Memory of a DCS Redis 3.0 Instance Smaller Than Instance Cache Size?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0730018.html">Why Is Available Memory Smaller Than Instance Cache Size?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730019.html">Does DCS for Redis Support Multiple Databases?</a></strong><br>
</li>
@ -26,8 +26,6 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730023.html">What Should I Do If an Error Occurs in Redis Exporter?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730024.html">Why Is Memory Usage More Than 100%?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730025.html">Why Is Redisson Distributed Lock Not Supported by DCS Proxy Cluster Redis 3.0 Instances?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730026.html">Can I Customize or Change the Port for Accessing a DCS Instance?</a></strong><br>
@ -40,8 +38,6 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730032.html">Does DCS for Redis Provide Backend Management Software?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730033.html">Why Is Memory of a DCS Redis Instance Used Up by Just a Few Keys?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730034.html">Can I Recover Data from Deleted DCS Instances?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-210223001.html">Why Is "Error in execution" Returned When I Access Redis?</a></strong><br>

4
docs/dcs/umn/dcs-faq-0326022.html
View File

@ -4,11 +4,11 @@
<div id="body8662426"></div>
<div>
<ul class="ullinks">
<li class="ulchildlink"><strong><a href="dcs-faq-0730043.html">Can DCS Redis Instances Be Upgraded, for Example, from Redis 3.0 to Redis 4.0 or 5.0?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0730043.html">Can DCS Redis Instances Be Upgraded, for Example, from Redis 4.0 to 5.0?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730044.html">Are Services Interrupted If Maintenance is Performed During the Maintenance Time Window?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730045.html">Are Instance Resources Affected During Specification Modification?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0730045.html">Are Instances Stopped or Restarted During Specification Modification?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730047.html">Are Services Interrupted During Specification Modification?</a></strong><br>
</li>

8
docs/dcs/umn/dcs-faq-0326024.html
View File

@ -8,7 +8,13 @@
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730054.html">Can I Export Backup Data of DCS Redis Instances to RDB Files Using the Console?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-0730057.html">Does DCS Support Data Persistence?</a></strong><br>
<li class="ulchildlink"><strong><a href="dcs-faq-0427081.html">Does DCS Support Data Persistence? What Is the Impact of Persistence?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-210706001.html">When Will AOF Rewrites Be Triggered?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-220317.html">Can I Migrate Data to Multiple Target Instances in One Migration Task?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-faq-11185.html">Will the Same Keys Be Overwritten During Data Migration or Backup Import?</a></strong><br>
</li>
<li class="ulchildlink"><strong><a href="dcs-migration-090626001.html">Online Migration with Rump</a></strong><br>
</li>

11
docs/dcs/umn/dcs-faq-0427005.html Normal file
View File

@ -0,0 +1,11 @@
<a name="dcs-faq-0427005"></a><a name="dcs-faq-0427005"></a>
<h1 class="topictitle1">Why Is "(error) NOAUTH Authentication required" Displayed When I Access a DCS Redis Instance?</h1>
<div id="body8662426"><p id="dcs-faq-0427005__en-us_topic_0000001198143749_p141551827153911">This is because you have enabled password-free access for the instance. To prevent the error message from appearing, do not enter any password.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326020.html">Client and Network Connection</a></div>
</div>
</div>

11
docs/dcs/umn/dcs-faq-0427015.html Normal file
View File

@ -0,0 +1,11 @@
<a name="dcs-faq-0427015"></a><a name="dcs-faq-0427015"></a>
<h1 class="topictitle1">Is a Password Required for Accessing an Instance? How Do I Set a Password?</h1>
<div id="body8662426"><ul id="dcs-faq-0427015__en-us_topic_0000001152024102_ul28501157135618"><li id="dcs-faq-0427015__en-us_topic_0000001152024102_li6850125725611">A DCS Redis instance can be access with or without a password. You can directly access a DCS Redis instance through a Redis client without setting a password. However, for security purposes, you are advised to set a password for authentication and verification whenever possible. The password must be set when you create the instance.</li><li id="dcs-faq-0427015__en-us_topic_0000001152024102_li1636793117431">To change the Redis instance access mode, or change or reset a password, see <a href="dcs-ug-0312039.html">Managing Passwords</a>.</li></ul>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326020.html">Client and Network Connection</a></div>
</div>
</div>

12
docs/dcs/umn/dcs-faq-0427057.html Normal file
View File

@ -0,0 +1,12 @@
<a name="dcs-faq-0427057"></a><a name="dcs-faq-0427057"></a>
<h1 class="topictitle1">Is There a Time Limit on Executing Redis Commands? What Will Happen If a Command Times Out?</h1>
<div id="body8662426"><p id="dcs-faq-0427057__en-us_topic_0000001198023667_p127571020163120">Redis command timeouts can be controlled on the client end or server end.</p>
<ul id="dcs-faq-0427057__en-us_topic_0000001198023667_ul12261193311317"><li id="dcs-faq-0427057__en-us_topic_0000001198023667_li7261183303115">Timeouts on the client end are controlled in the client code. You can determine the timeouts that suit service needs. For example, if you use Lettuce, a Java client, configure the <strong id="dcs-faq-0427057__en-us_topic_0000001198023667_b11785832605555">timeout</strong> parameter.</li><li id="dcs-faq-0427057__en-us_topic_0000001198023667_li1368413512311">On the server end, the <strong id="dcs-faq-0427057__en-us_topic_0000001198023667_b14521440025555">timeout</strong> parameter is set to <strong id="dcs-faq-0427057__en-us_topic_0000001198023667_b18874047065555">0</strong> by default, indicating that connections will never be terminated. Modify the parameter setting by referring to <a href="dcs-ug-0312024.html">Modifying Configuration Parameters</a>.</li></ul>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-190921003.html">Redis Commands</a></div>
</div>
</div>

11
docs/dcs/umn/dcs-faq-0427058.html Normal file
View File

@ -0,0 +1,11 @@
<a name="dcs-faq-0427058"></a><a name="dcs-faq-0427058"></a>
<h1 class="topictitle1">Can I Configure Redis Keys to Be Case-Insensitive?</h1>
<div id="body8662426"><p id="dcs-faq-0427058__en-us_topic_0000001198023663_p10599125583514">No. Like in open-source Redis, keys in DCS for Redis are case-sensitive and cannot be configured to be case-insensitive.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-190921003.html">Redis Commands</a></div>
</div>
</div>

22
docs/dcs/umn/dcs-faq-0427081.html Normal file
View File

@ -0,0 +1,22 @@
<a name="dcs-faq-0427081"></a><a name="dcs-faq-0427081"></a>
<h1 class="topictitle1">Does DCS Support Data Persistence? What Is the Impact of Persistence?</h1>
<div id="body8662426"><div class="section" id="dcs-faq-0427081__en-us_topic_0000001152024118_section54961613182719"><h4 class="sectiontitle">Support for Persistence</h4><ul id="dcs-faq-0427081__en-us_topic_0000001152024118_ul13785171114168"><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li12785181119169">DCS Redis instances:<ul id="dcs-faq-0427081__en-us_topic_0000001152024118_ul8386756113825"><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li40228198113825">Single-node: Data persistence is not supported.</li><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li43901409113836">Master/standby and cluster (except single-replica clusters): Data persistence is supported.</li></ul>
</li></ul>
</div>
<div class="section" id="dcs-faq-0427081__en-us_topic_0000001152024118_section7456131223018"><h4 class="sectiontitle">Persistence Modes</h4><ul id="dcs-faq-0427081__en-us_topic_0000001152024118_ul8704048102717"><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li16479171616113">DCS supports only AOF persistence by default. You can enable or disable persistence as required. All instances except single-node and single-replica cluster ones are created with AOF persistence enabled.</li><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li20704144872715">DCS does not support RDB persistence by default and you cannot configure the <strong id="dcs-faq-0427081__en-us_topic_0000001152024118_b10732728165418">save</strong> parameter. If RDB persistence is required for a master/standby or cluster instance of Redis 4.0 or later, you can use the backup and restoration function to back up the instance data to an RDB file and store the data in OBS.</li></ul>
</div>
<div class="section" id="dcs-faq-0427081__en-us_topic_0000001152024118_section1456541017316"><h4 class="sectiontitle">Disk Used for Persistence</h4><p id="dcs-faq-0427081__en-us_topic_0000001152024118_p13729156103118">For DCS Redis 4.0 and later instances, data is persisted to SSD disks.</p>
</div>
<div class="section" id="dcs-faq-0427081__en-us_topic_0000001152024118_section1530716418282"><h4 class="sectiontitle">Impact of AOF Persistence</h4><div class="p" id="dcs-faq-0427081__en-us_topic_0000001152024118_p154892314174">After AOF persistence is enabled, the Redis-Server process needs to record operations in the AOF file for data persistence.<ul id="dcs-faq-0427081__en-us_topic_0000001152024118_ul1986274393117"><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li3321124219310">If the disk or I/O of the underlying compute node is faulty, the latency may increase or a master/standby switchover may occur.</li><li id="dcs-faq-0427081__en-us_topic_0000001152024118_li415512683212">Redis-Server periodically rewrites the AOF. During a rewrite, the latency may be high for a short time. For details about the AOF rewriting rules, see <a href="dcs-faq-210706001.html">When Will AOF Rewrites Be Triggered?</a></li></ul>
</div>
<p id="dcs-faq-0427081__en-us_topic_0000001152024118_p2024623618266">If DCS instances are used to accelerate applications, you are advised to disable persistence for higher performance and stability. Exercise caution when disabling persistence. Without persistence, cached data may be lost in extreme scenarios (for example, when both the master and standby nodes are faulty).</p>
<p id="dcs-faq-0427081__en-us_topic_0000001152024118_p13246173612268">To disable AOF persistence, set parameter <strong id="dcs-faq-0427081__en-us_topic_0000001152024118_b158831227155919">appendonly</strong> to <strong id="dcs-faq-0427081__en-us_topic_0000001152024118_b488312785910">no</strong> on the instance details page.</p>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326024.html">Data Backup, Export, and Migration</a></div>
</div>
</div>

2
docs/dcs/umn/dcs-faq-0521003.html
View File

@ -26,7 +26,7 @@
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></div>
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></div>
</div>
</div>

2
docs/dcs/umn/dcs-faq-0521004.html
View File

@ -54,7 +54,7 @@
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></div>
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></div>
</div>
</div>

2
docs/dcs/umn/dcs-faq-0521005.html
View File

@ -38,7 +38,7 @@
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></div>
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></div>
</div>
</div>

2
docs/dcs/umn/dcs-faq-0521006.html
View File

@ -11,7 +11,7 @@
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></div>
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></div>
</div>
</div>

4
docs/dcs/umn/dcs-faq-0603001.html
View File

@ -1,7 +1,9 @@
<a name="dcs-faq-0603001"></a><a name="dcs-faq-0603001"></a>
<h1 class="topictitle1">Why Is the Rejected Connections Metric Displayed?</h1>
<div id="body8662426"><p id="dcs-faq-0603001__en-us_topic_0000001198023693_p73321412506">If the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b10926205117259">Rejected Connections</strong> metric is displayed, check if the number of connected clients exceeds the maximum allowed number of connections of the instances. To check the maximum allowed number of connections, go to the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b143881647112614">Parameters</strong> tab page of the instance and check the value of the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b19671140122712">maxclients</strong> parameter.</p>
<div id="body8662426"><p id="dcs-faq-0603001__en-us_topic_0000001198023693_p490381214435">If the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b98701745355210">Rejected Connections</strong> metric is displayed, check if the number of connected clients exceeds the maximum allowed number of connections of the instances.</p>
<ul id="dcs-faq-0603001__en-us_topic_0000001198023693_ul62821695257"><li id="dcs-faq-0603001__en-us_topic_0000001198023693_li3282899258">To check the maximum allowed number of connections, go to the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b18884174881">Parameters</strong> tab page of the instance and check the value of the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b588474885">maxclients</strong> parameter. (Proxy Cluster instances do not have this parameter. You can view the maximum number of connections on the instance creation page.)</li><li id="dcs-faq-0603001__en-us_topic_0000001198023693_li92826922519">To check the current number of connections, go to the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b25901273816">Performance Monitoring</strong> tab page of the instance and check the <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b1859012271981">Connected Clients</strong> metric.</li></ul>
<p id="dcs-faq-0603001__en-us_topic_0000001198023693_p1375612232417">If the current number of connections reaches the upper limit, you can adjust the value of <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b21271135920">maxclients</strong>. If the value of <strong id="dcs-faq-0603001__en-us_topic_0000001198023693_b7602223799">maxclients</strong> can no longer be increased, increase the instance specifications.</p>
</div>
<div>
<div class="familylinks">

4
docs/dcs/umn/dcs-faq-0606002.html
View File

@ -10,7 +10,7 @@
</thead>
<tbody><tr id="dcs-faq-0606002__row1980212370326"><td class="cellrowborder" valign="top" width="34.96%" headers="mcps1.3.1.1.3.1.1 "><p id="dcs-faq-0606002__p1980293733210">Through <strong id="dcs-faq-0606002__b79321032553939">Big Key Analysis</strong> and <strong id="dcs-faq-0606002__b103292901953939">Hot Key Analysis</strong> on the DCS console</p>
</td>
<td class="cellrowborder" valign="top" width="65.03999999999999%" headers="mcps1.3.1.1.3.1.2 "><p id="dcs-faq-0606002__p1582215495119">See <a href="dcs-ug-190808001.html">Cache Analysis</a>.</p>
<td class="cellrowborder" valign="top" width="65.03999999999999%" headers="mcps1.3.1.1.3.1.2 "><p id="dcs-faq-0606002__p1582215495119">See <a href="dcs-ug-190808001.html">Analyzing Big Keys and Hot Keys</a>.</p>
</td>
</tr>
<tr id="dcs-faq-0606002__row38022037183218"><td class="cellrowborder" valign="top" width="34.96%" headers="mcps1.3.1.1.3.1.1 "><p id="dcs-faq-0606002__p12802137113218">By using the <strong id="dcs-faq-0606002__b1859015253209">bigkeys</strong> and <strong id="dcs-faq-0606002__b1659014257208">hotkeys</strong> options on redis-cli</p>
@ -29,7 +29,7 @@
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Analysis of Big Keys and Hot Keys</a></div>
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0805001.html">Big/Hot Key Analysis</a></div>
</div>
</div>

11
docs/dcs/umn/dcs-faq-0624001.html Normal file
View File

@ -0,0 +1,11 @@
<a name="dcs-faq-0624001"></a><a name="dcs-faq-0624001"></a>
<h1 class="topictitle1">Can I View the Most Frequently Used Redis Commands?</h1>
<div id="body8662426"><p id="dcs-faq-0624001__en-us_topic_0000001198023703_p8060118">No. Redis does not record commands and does not support viewing the most frequently used commands.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-190921003.html">Redis Commands</a></div>
</div>
</div>

3
docs/dcs/umn/dcs-faq-0730001.html
View File

@ -1,8 +1,7 @@
<a name="dcs-faq-0730001"></a><a name="dcs-faq-0730001"></a>
<h1 class="topictitle1">Does DCS Support Public Access?</h1>
<h1 class="topictitle1">Does DCS Support Access over Public Networks?</h1>
<div id="body1596093268949"><p id="dcs-faq-0730001__p151602565397">No. DCS instances cannot be access at their EIPs over public networks. To ensure security, the ECS that serves as a client and the DCS instance that the client will access must belong to the same VPC.</p>
<p id="dcs-faq-0730001__p938602954013">In the application development and debugging phase, you can also use an SSH agent to access DCS instances in the local environment.</p>
</div>
<div>
<div class="familylinks">

1
docs/dcs/umn/dcs-faq-0730005.html
View File

@ -3,6 +3,7 @@
<h1 class="topictitle1">Why Do Requests Sometimes Time Out in Clients?</h1>
<div id="body1596093268949"><p id="dcs-faq-0730005__en-us_topic_0152099099_p981859161814">Occasional timeout errors are normal because of network connectivity and client timeout configurations.</p>
<p id="dcs-faq-0730005__en-us_topic_0152099099_p253031016162">You are advised to include reconnection operations into your service code to avoid service failure if a single request fails.</p>
<p id="dcs-faq-0730005__p442954418318">If a connection request times out, check if AOF persistence has been enabled. To avoid blocking, ensure that AOF has been enabled.</p>
<p id="dcs-faq-0730005__en-us_topic_0152099099_p1453020105168">If timeout errors occur frequently, contact O&amp;M personnel.</p>
</div>
<div>

2
docs/dcs/umn/dcs-faq-0730006.html
View File

@ -4,7 +4,7 @@
<div id="body1596093268949"><p id="dcs-faq-0730006__en-us_topic_0152099099_p1038812015818">The error message that will possibly be displayed when you <span class="keyword" id="dcs-faq-0730006__keyword39817314147">use the Jedis connection pool</span> is as follows:</p>
<pre class="screen" id="dcs-faq-0730006__en-us_topic_0152099099_screen2398182394217">redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool</pre>
<p id="dcs-faq-0730006__en-us_topic_0152099099_p129321946103813">If this error message is displayed, check whether your instance is running properly. If it is running properly, perform the following checks:</p>
<ol id="dcs-faq-0730006__en-us_topic_0152099099_ol980141914912"><li id="dcs-faq-0730006__en-us_topic_0152099099_li10802819590"><span>Network</span><p><ol type="a" id="dcs-faq-0730006__en-us_topic_0152099099_ol4963821184719"><li id="dcs-faq-0730006__en-us_topic_0152099099_li3963182119479">Check the IP address configurations.<p id="dcs-faq-0730006__en-us_topic_0152099099_p173211526174712"><a name="dcs-faq-0730006__en-us_topic_0152099099_li3963182119479"></a><a name="en-us_topic_0152099099_li3963182119479"></a>Check whether the IP address configured on the <span class="keyword" id="dcs-faq-0730006__keyword324316961418">Jedis client</span> is the same as the subnet address configured for your DCS instance. </p>
<ol id="dcs-faq-0730006__en-us_topic_0152099099_ol980141914912"><li id="dcs-faq-0730006__en-us_topic_0152099099_li10802819590"><span>Network</span><p><ol type="a" id="dcs-faq-0730006__en-us_topic_0152099099_ol4963821184719"><li id="dcs-faq-0730006__en-us_topic_0152099099_li3963182119479">Check the IP address configurations.<p id="dcs-faq-0730006__en-us_topic_0152099099_p173211526174712"><a name="dcs-faq-0730006__en-us_topic_0152099099_li3963182119479"></a><a name="en-us_topic_0152099099_li3963182119479"></a>Check whether the IP address configured on the <span class="keyword" id="dcs-faq-0730006__keyword16398923458">Jedis client</span> is the same as the subnet address configured for your DCS instance.</p>
</li><li id="dcs-faq-0730006__en-us_topic_0152099099_li99631217478">Test the network.<p id="dcs-faq-0730006__en-us_topic_0152099099_p113161961483"><a name="dcs-faq-0730006__en-us_topic_0152099099_li99631217478"></a><a name="en-us_topic_0152099099_li99631217478"></a>Use the ping command and telnet on the client to test the network.</p>
<ul id="dcs-faq-0730006__en-us_topic_0152099099_ul97951811705"><li id="dcs-faq-0730006__en-us_topic_0152099099_li6637143813114">If the network cannot be pinged:<p id="dcs-faq-0730006__p8645128191212"><a name="dcs-faq-0730006__en-us_topic_0152099099_li6637143813114"></a><a name="en-us_topic_0152099099_li6637143813114"></a>For intra-VPC access to a DCS Redis 3.0 instance, ensure that the client and your DCS instance belong to the same VPC and security group, or the security group of your DCS instance allows access through port 6379. For details, see <a href="en-us_topic_0090662012.html">Security Group Configurations</a>.</p>
</li><li id="dcs-faq-0730006__en-us_topic_0152099099_li1799555071112">If the IP address can be pinged but telnet failed, restart your instance. If the problem persists after the restart, contact technical support.</li></ul>

2
docs/dcs/umn/dcs-faq-0730008.html
View File

@ -1,7 +1,7 @@
<a name="dcs-faq-0730008"></a><a name="dcs-faq-0730008"></a>
<h1 class="topictitle1">How Do I Access a DCS Redis Instance Through Redis Desktop Manager?</h1>
<div id="body1596093268949"><p id="dcs-faq-0730008__en-us_topic_0152099099_p412722720489">You can access a DCS Redis instance through the Redis Desktop Manager within a VPC.</p>
<div id="body1596093268949"><p id="dcs-faq-0730008__en-us_topic_0152099099_p412722720489"><strong id="dcs-faq-0730008__b192947387516">You can access a DCS Redis instance through the Redis Desktop Manager within a VPC.</strong></p>
<ol id="dcs-faq-0730008__en-us_topic_0152099099_ol107224124413"><li id="dcs-faq-0730008__en-us_topic_0152099099_li137824154420">Enter the address, port number (6379), and authentication password of the DCS instance you want to access.</li><li id="dcs-faq-0730008__en-us_topic_0152099099_li1910315304440">Click <strong id="dcs-faq-0730008__b129991046205816">Test Connection</strong>.<p id="dcs-faq-0730008__en-us_topic_0152099099_p93523294415">The system displays a success message if the connection is successful.</p>
<div class="fignone" id="dcs-faq-0730008__en-us_topic_0152099099_fig1917118510459"><span class="figcap"><b>Figure 1 </b>Accessing a DCS Redis instance through Redis Desktop Manager over the intranet</span><br><span><img id="dcs-faq-0730008__en-us_topic_0152099099_image16136128151012" src="en-us_image_0266315618.png"></span></div>
<div class="note" id="dcs-faq-0730008__en-us_topic_0152099099_note699593614451"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><p id="dcs-faq-0730008__en-us_topic_0152099099_p199951336184515">When accessing a cluster DCS instance, the Redis command is run properly, but an error message may display on the left because DCS clusters are based on Codis, which differs from the native Redis in terms of the <strong id="dcs-faq-0730008__b9796125355818">INFO</strong> command output.</p>

2
docs/dcs/umn/dcs-faq-0730010.html
View File

@ -8,7 +8,7 @@
</li><li id="dcs-faq-0730010__en-us_topic_0152099099_li1017384662415">Check if the maximum bandwidth has been reached.<p id="dcs-faq-0730010__en-us_topic_0152099099_p1797526102510"><a name="dcs-faq-0730010__en-us_topic_0152099099_li1017384662415"></a><a name="en-us_topic_0152099099_li1017384662415"></a>If the bandwidth reaches the maximum bandwidth for the corresponding instance specifications, Redis connections may time out.</p>
</li><li id="dcs-faq-0730010__en-us_topic_0152099099_li1846772016228">For a DCS Redis 3.0 instance, check the inbound access rules of the security group.<p id="dcs-faq-0730010__en-us_topic_0152099099_p14645112182815"><a name="dcs-faq-0730010__en-us_topic_0152099099_li1846772016228"></a><a name="en-us_topic_0152099099_li1846772016228"></a>Intra-VPC access: If the Redis client and the Redis instance are bound with different security groups, allow inbound access over port 6379 for the security group of the instance.</p>
<p id="dcs-faq-0730010__p14803202620398">For details, see <a href="en-us_topic_0090662012.html">Security Group Configurations</a>.</p>
</li><li id="dcs-faq-0730010__li2046822714264">For a DCS Redis 4.0 or 5.0 instance, check the whitelist configuration.<p id="dcs-faq-0730010__p86935385270"><a name="dcs-faq-0730010__li2046822714264"></a><a name="li2046822714264"></a>If the instance has a whitelist, ensure that the client IP address is included in the whitelist. Otherwise, the connection will fail.</p>
</li><li id="dcs-faq-0730010__li2046822714264">For a DCS Redis 4.0/5.0/6.0 instance, check the whitelist configuration.<p id="dcs-faq-0730010__p86935385270"><a name="dcs-faq-0730010__li2046822714264"></a><a name="li2046822714264"></a>If the instance has a whitelist, ensure that the client IP address is included in the whitelist. Otherwise, the connection will fail.</p>
<p id="dcs-faq-0730010__p1429974202718">For details, see <a href="dcs-ug-190812001.html">Managing IP Address Whitelist</a>.</p>
<p id="dcs-faq-0730010__p13299216102715">If the client IP address has changed, add the new IP address to the whitelist.</p>
</li><li id="dcs-faq-0730010__en-us_topic_0152099099_li10464192019419">Check the configuration parameter <strong id="dcs-faq-0730010__b13215165255914">notify-keyspace-events</strong>.<p id="dcs-faq-0730010__en-us_topic_0152099099_p66120341344">Set <strong id="dcs-faq-0730010__b1961115532594">notify-keyspace-events</strong> to <strong id="dcs-faq-0730010__b1761113531598">Egx</strong>.</p>

6
docs/dcs/umn/dcs-faq-0730014.html
View File

@ -1,8 +1,8 @@
<a name="dcs-faq-0730014"></a><a name="dcs-faq-0730014"></a>
<h1 class="topictitle1">Why Aren't Security Groups Configured for DCS Redis 4.0 and 5.0 Instances?</h1>
<div id="body1596093268949"><p id="dcs-faq-0730014__en-us_topic_0152099097_p16123134244116">Currently, DCS Redis 4.0 and Redis 5.0 instances use VPC endpoints and do not support security groups. You can configure whitelists instead. For details, see <a href="dcs-ug-190812001.html">Managing IP Address Whitelist</a>.</p>
<p id="dcs-faq-0730014__p167460299191">To allow access only from specific IP addresses to a DCS Redis 4.0 or 5.0 instance, add the IP addresses to the instance whitelist.</p>
<h1 class="topictitle1">Why Aren't Security Groups Configured for DCS Redis 4.0/5.0/6.0 Instances?</h1>
<div id="body1596093268949"><p id="dcs-faq-0730014__en-us_topic_0152099097_p16123134244116">Currently, DCS Redis 4.0/5.0/6.0 instances use VPC endpoints and do not support security groups. You can configure whitelists instead. For details, see <a href="dcs-ug-190812001.html">Managing IP Address Whitelist</a>.</p>
<p id="dcs-faq-0730014__p167460299191">To allow access only from specific IP addresses to a DCS Redis instance, add the IP addresses to the instance whitelist.</p>
<p id="dcs-faq-0730014__p8907193444015">If no whitelists are added to the instance whitelist or the whitelist function is disabled, all IP addresses that can communicate with the VPC can access the instance.</p>
</div>
<div>

2
docs/dcs/umn/dcs-faq-0730017.html
View File

@ -2,7 +2,7 @@
<h1 class="topictitle1">Can I Obtain the Addresses of the Nodes in a Cluster DCS Redis Instance?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730017__en-us_topic_0152099097_p1483584313321">Cluster DCS Redis 3.0 instances (Proxy Cluster type) are used in the same way that you use single-node or master/standby instances. You do not need to know the backend node addresses.</p>
<p id="dcs-faq-0730017__en-us_topic_0152099097_p1835134343213">For a cluster DCS Redis 4.0 or 5.0 instance (Redis Cluster type), run the <strong id="dcs-faq-0730017__b16188355307">CLUSTER NODES</strong> command to obtain node addresses:</p>
<p id="dcs-faq-0730017__en-us_topic_0152099097_p1835134343213">For a cluster DCS Redis 4.0/5.0/ instance (Redis Cluster type), run the <strong id="dcs-faq-0730017__b16188355307">CLUSTER NODES</strong> command to obtain node addresses:</p>
<p id="dcs-faq-0730017__en-us_topic_0152099097_p64034338434"><strong id="dcs-faq-0730017__en-us_topic_0152099097_b1740393319431">redis-cli -h <em id="dcs-faq-0730017__en-us_topic_0152099097_i174031933184315">{redis_address}</em> -p <em id="dcs-faq-0730017__en-us_topic_0152099097_i44036333433">{redis_port}</em> -a <em id="dcs-faq-0730017__en-us_topic_0152099097_i184031833204314">{redis_password}</em> cluster nodes</strong></p>
<p id="dcs-faq-0730017__en-us_topic_0152099097_p12403163316433">In the output similar to the following, obtain the IP addresses and port numbers of all the master nodes.</p>
<p id="dcs-faq-0730017__en-us_topic_0152099097_p9149163917382"><span><img id="dcs-faq-0730017__en-us_topic_0152099097_image19820346211" src="en-us_image_0266316213.png"></span></p>

4
docs/dcs/umn/dcs-faq-0730018.html
View File

@ -1,7 +1,7 @@
<a name="dcs-faq-0730018"></a><a name="dcs-faq-0730018"></a>
<h1 class="topictitle1">Why Is Available Memory of a DCS Redis 3.0 Instance Smaller Than Instance Cache Size?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730018__en-us_topic_0152099097_p1131455111168">DCS Redis 3.0 instances are deployed on VMs and some memory is reserved for system overheads.</p>
<h1 class="topictitle1">Why Is Available Memory Smaller Than Instance Cache Size?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730018__en-us_topic_0152099097_p1131455111168">DCS Redis 3.0 instances are deployed on VMs and some memory is reserved for system overheads. This problem will not occur on other instance versions.</p>
</div>
<div>
<div class="familylinks">

2
docs/dcs/umn/dcs-faq-0730021.html
View File

@ -1,7 +1,7 @@
<a name="dcs-faq-0730021"></a><a name="dcs-faq-0730021"></a>
<h1 class="topictitle1">Does DCS for Redis Support Sentinel?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730021__en-us_topic_0152099097_p047315232012">Yes. Redis Sentinel is supported by DCS for Redis 4.0 and 5.0 and is enabled by default. Sentinel constantly checks if master and replica nodes are running properly. If the master is not running properly, Sentinel starts a failover process and promotes a replica to master.</p>
<div id="body1596093268950"><p id="dcs-faq-0730021__en-us_topic_0152099097_p047315232012">Cluster instances and master/standby DCS Redis 4.0/5.0/6.0 instances support Sentinels. Sentinels monitor the running status of both the master and standby nodes of a master/standby instance and each shard of a cluster instance. If the master node becomes faulty, a failover will be performed.</p>
<p id="dcs-faq-0730021__en-us_topic_0152099097_p74691819125910">However, DCS for Redis 3.0 does not support Redis Sentinel. Instead, it uses keepalive to monitor master and replica nodes and to manage failovers.</p>
</div>
<div>

7
docs/dcs/umn/dcs-faq-0730023.html
View File

@ -2,7 +2,12 @@
<h1 class="topictitle1">What Should I Do If an Error Occurs in Redis Exporter?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730023__en-us_topic_0152099097_p367417420511">Start the Redis exporter using the CLI. Based on the output, check for errors and troubleshoot accordingly.</p>
<p id="dcs-faq-0730023__en-us_topic_0152099097_p17674142145114"><span><img id="dcs-faq-0730023__en-us_topic_0152099097_image267410421514" src="en-us_image_0266316214.jpg"></span></p>
<pre class="screen" id="dcs-faq-0730023__screen8713236352">[root@ecs-swk /]./redis_exporter -redis.addr 192.168.0.23:6379
INFO[0000] Redis Metrics Exporter V0.15.0 build date:2018-01-19-04:08:01 sha1: a0d9ec4704b4d35cd08544d395038f417716a03a
Go:go1.9.2
INFO[0000] Providing metrics at :9121/metrics
INFO[0000] Connecting to redis hosts: []string{192.168.0.23:6379}
INFO[0000] Using alias:[]string{""}</pre>
</div>
<div>
<div class="familylinks">

11
docs/dcs/umn/dcs-faq-0730024.html
View File

@ -1,11 +0,0 @@
<a name="dcs-faq-0730024"></a><a name="dcs-faq-0730024"></a>
<h1 class="topictitle1">Why Is Memory Usage More Than 100%?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730024__en-us_topic_0152099097_p1212493273818">This is normal due to Redis functions (such as master/replica replication and lazyfree). When the memory becomes full, scale up the instance or remove unnecessary data.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326021.html">Redis Usage</a></div>
</div>
</div>

6
docs/dcs/umn/dcs-faq-0730026.html
View File

@ -1,9 +1,9 @@
<a name="dcs-faq-0730026"></a><a name="dcs-faq-0730026"></a>
<h1 class="topictitle1">Can I Customize or Change the Port for Accessing a DCS Instance?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730026__p15703171835620">You cannot customize or change the port for accessing a DCS Redis 3.0 instance. You can customize and change the port for accessing a DCS Redis 4.0 or 5.0 instance.</p>
<ul id="dcs-faq-0730026__en-us_topic_0152099097_ul2099115517587"><li id="dcs-faq-0730026__en-us_topic_0152099097_li399125535811">Redis 3.0<p id="dcs-faq-0730026__en-us_topic_0152099097_p851518115910"><a name="dcs-faq-0730026__en-us_topic_0152099097_li399125535811"></a><a name="en-us_topic_0152099097_li399125535811"></a>Use port 6379 for intra-VPC access.</p>
</li><li id="dcs-faq-0730026__en-us_topic_0152099097_li1188105085912">Redis 4.0 and Redis 5.0<p id="dcs-faq-0730026__en-us_topic_0152099097_p12318114516310"><a name="dcs-faq-0730026__en-us_topic_0152099097_li1188105085912"></a><a name="en-us_topic_0152099097_li1188105085912"></a>You can specify a port (ranging from 1 to 65535) or use the default port (6379) for accessing a DCS Redis 4.0 or 5.0 instance. If no port is specified, the default port will be used.</p>
<div id="body1596093268950"><p id="dcs-faq-0730026__p15703171835620">You cannot customize or change the port for accessing a DCS Redis 3.0 instance. You can customize (during instance creation) but cannot change the port for accessing a DCS Redis 4.0 or later instance.</p>
<ul id="dcs-faq-0730026__en-us_topic_0152099097_ul2099115517587"><li id="dcs-faq-0730026__en-us_topic_0152099097_li399125535811">Redis 3.0<p id="dcs-faq-0730026__en-us_topic_0152099097_p851518115910"><a name="dcs-faq-0730026__en-us_topic_0152099097_li399125535811"></a><a name="en-us_topic_0152099097_li399125535811"></a>Intra-VPC access: port 6379.</p>
</li><li id="dcs-faq-0730026__en-us_topic_0152099097_li1188105085912">Redis 4.0 and later<p id="dcs-faq-0730026__en-us_topic_0152099097_p12318114516310"><a name="dcs-faq-0730026__en-us_topic_0152099097_li1188105085912"></a><a name="en-us_topic_0152099097_li1188105085912"></a>You can specify a port (ranging from 1 to 65535) or use the default port (6379) for accessing an instance. If no port is specified, the default port will be used.</p>
</li></ul>
<p id="dcs-faq-0730026__p14803202620398">If the instance and the client use different security groups, you must configure access rules for the security groups, allowing access through the specified port. For details, see <a href="en-us_topic_0090662012.html">Security Group Configurations</a>.</p>
</div>

3
docs/dcs/umn/dcs-faq-0730027.html
View File

@ -1,7 +1,8 @@
<a name="dcs-faq-0730027"></a><a name="dcs-faq-0730027"></a>
<h1 class="topictitle1">Can I Modify the Connection Addresses for Accessing a DCS Instance?</h1>
<div id="body1596093268950"><p id="dcs-faq-0730027__en-us_topic_0152099097_p1482255016399">After a DCS instance is created, its intra-VPC connection addresses cannot be modified.</p>
<div id="body1596093268950"><p id="dcs-faq-0730027__en-us_topic_0152099097_p1482255016399">After a DCS instance is created, its intra-VPC connection addresses cannot be modified. </p>
<p id="dcs-faq-0730027__p14629113519598">To use a different IP address, you must create a new instance and manually specify an IP address. After the instance is created, migrate the data from the old instance to the new instance.</p>
<p id="dcs-faq-0730027__en-us_topic_0152099097_p1858864302818">For details about accessing DCS instances through clients, see <a href="dcs-ug-0326009.html">Accessing a DCS Redis Instance Through redis-cli</a>.</p>
</div>
<div>

12
docs/dcs/umn/dcs-faq-0730033.html
View File

@ -1,12 +0,0 @@
<a name="dcs-faq-0730033"></a><a name="dcs-faq-0730033"></a>
<h1 class="topictitle1">Why Is Memory of a DCS Redis Instance Used Up by Just a Few Keys?</h1>
<div id="body1596093268951"><p id="dcs-faq-0730033__en-us_topic_0152099097_p1559974945710">Possible cause: The output buffer may have occupied an excessive amount of memory.</p>
<p id="dcs-faq-0730033__en-us_topic_0152099097_p26117919543">Solution: After connecting to the instance using redis-cli, run the <strong id="dcs-faq-0730033__b964793993117">redis-cli --bigkeys</strong> command to scan for big keys. Then, run the <strong id="dcs-faq-0730033__b16648143913317">info</strong> command to check the output buffer size.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326021.html">Redis Usage</a></div>
</div>
</div>

4
docs/dcs/umn/dcs-faq-0730034.html
View File

@ -2,7 +2,9 @@
<h1 class="topictitle1">Can I Recover Data from Deleted DCS Instances?</h1>
<div id="body1596093268951"><p id="dcs-faq-0730034__en-us_topic_0152099097_p1631651782618">If a DCS instance is automatically deleted or manually deleted through the Redis client, its data cannot be retrieved. If you have backed up the instance, you can restore its data from the backup. However, the restoration will overwrite the data written in during the period from the backup and the restoration.</p>
<p id="dcs-faq-0730034__en-us_topic_0152099097_p16241771816">By default, data is not evicted from DCS instances. You can modify the instance configuration parameters to adjust the eviction policy so that the instance can evict key values.</p>
<p id="dcs-faq-0730034__p3823245101117">You can restore backup data to a master/standby cluster, or instance through <strong id="dcs-faq-0730034__b119161431502">Backups &amp; Restorations</strong> on the DCS console. For details, see <a href="dcs-ug-0312033.html">Restoring a DCS Instance</a>.</p>
<p id="dcs-faq-0730034__en-us_topic_0152099097_p16241771816"></p>
<p id="dcs-faq-0730034__p1195017431792">If a DCS instance is deleted, the instance data and its backup will also be deleted. Before deleting an instance, you can download the backup files of the instance for permanent local storage and can also migrate them to a new instance if you need to restore the data. For details about how to download the backup data, see <a href="dcs-ug-0312034.html">Downloading a Backup File</a></p>
</div>
<div>
<div class="familylinks">

4
docs/dcs/umn/dcs-faq-0730036.html
View File

@ -5,9 +5,9 @@
<ul id="dcs-faq-0730036__ul5345182618333"><li id="dcs-faq-0730036__li1345132623311">Redis 3.0<p id="dcs-faq-0730036__p10964478357"><a name="dcs-faq-0730036__li1345132623311"></a><a name="li1345132623311"></a>Data of a DCS Redis 3.0 instance cannot be cleared on the console, and can only be cleared by the <strong id="dcs-faq-0730036__b689814018266">FLUSHDB</strong> or <strong id="dcs-faq-0730036__b3166163914269">FLUSHALL</strong> command in redis-cli.</p>
<p id="dcs-faq-0730036__p8472203333612">Run the <strong id="dcs-faq-0730036__b13145640878138">FLUSHALL</strong> command to clear all the data in the instance.</p>
<p id="dcs-faq-0730036__p647293333619">Run the <strong id="dcs-faq-0730036__b12348169898138">FLUSHDB</strong> command to clear the data in the currently selected DB.</p>
</li><li id="dcs-faq-0730036__li18813103819364">Redis 4.0 and 5.0<p id="dcs-faq-0730036__p1515135633616"><a name="dcs-faq-0730036__li18813103819364"></a><a name="li18813103819364"></a>To clear data of a DCS Redis 4.0 or 5.0 instance, you can run the <strong id="dcs-faq-0730036__b3485143010548">FLUSHDB</strong> or <strong id="dcs-faq-0730036__b124911430165419">FLUSHALL</strong> command in redis-cli, use the data clearing function on the DCS console, or run the <strong id="dcs-faq-0730036__b1676102514715">FLUSHDB</strong> command on Web CLI.</p>
</li><li id="dcs-faq-0730036__li18813103819364">Redis 4.0/5.0/6.0<p id="dcs-faq-0730036__p1515135633616"><a name="dcs-faq-0730036__li18813103819364"></a><a name="li18813103819364"></a>To clear data of a DCS Redis 4.0/5.0/6.0 instance, you can run the <strong id="dcs-faq-0730036__b3485143010548">FLUSHDB</strong> or <strong id="dcs-faq-0730036__b124911430165419">FLUSHALL</strong> command in redis-cli, use the data clearing function on the DCS console, or run the <strong id="dcs-faq-0730036__b1676102514715">FLUSHDB</strong> command on Web CLI.</p>
<p id="dcs-faq-0730036__p963916114382">To clear data of a Redis Cluster instance, run the <strong id="dcs-faq-0730036__b9521924153015">FLUSHDB</strong> or <strong id="dcs-faq-0730036__b431212296307">FLUSHALL</strong> command on every shard of the instance. Otherwise, data may not be completely cleared.</p>
<div class="note" id="dcs-faq-0730036__note168212515318"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="dcs-faq-0730036__ul191791322143115"><li id="dcs-faq-0730036__li111791022143119">Currently, only DCS Redis 4.0 and 5.0 instances support data clearing by using the DCS console and by running the <strong id="dcs-faq-0730036__b263057135217">FLUSHDB</strong> command on Web CLI.</li><li id="dcs-faq-0730036__li13479118163312">When you run the <strong id="dcs-faq-0730036__b17668192510264">FLUSHDB</strong> command on Web CLI, only one shard is cleared at a time. If there are multiple shards, connect to and run the <strong id="dcs-faq-0730036__b16265133815350">FLUSHDB</strong> command on each master node.</li><li id="dcs-faq-0730036__li1079819242316">Redis Cluster data cannot be cleared by using Web CLI.</li></ul>
<div class="note" id="dcs-faq-0730036__note168212515318"><img src="public_sys-resources/note_3.0-en-us.png"><span class="notetitle"> </span><div class="notebody"><ul id="dcs-faq-0730036__ul191791322143115"><li id="dcs-faq-0730036__li111791022143119">Currently, only DCS Redis 4.0 and later instances support data clearing by using the DCS console and by running the <strong id="dcs-faq-0730036__b263057135217">FLUSHDB</strong> command on Web CLI.</li><li id="dcs-faq-0730036__li13479118163312">When you run the <strong id="dcs-faq-0730036__b17668192510264">FLUSHDB</strong> command on Web CLI, only one shard is cleared at a time. If there are multiple shards, connect to and run the <strong id="dcs-faq-0730036__b16265133815350">FLUSHDB</strong> command on each master node.</li><li id="dcs-faq-0730036__li1079819242316">Redis Cluster data cannot be cleared by using Web CLI.</li></ul>
</div></div>
</li></ul>
</div>

6
docs/dcs/umn/dcs-faq-0730040.html
View File

@ -2,7 +2,11 @@
<h1 class="topictitle1">Why Do I Fail to Execute Some Redis Commands?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730040__en-us_topic_0192035902_p8060118">Possible causes include the following:</p>
<ul id="dcs-faq-0730040__en-us_topic_0192035902_ul18525838123819"><li id="dcs-faq-0730040__en-us_topic_0192035902_li6525163893815">The command is incorrect.</li><li id="dcs-faq-0730040__en-us_topic_0192035902_li14525133819383">The command is disabled in DCS.<p id="dcs-faq-0730040__en-us_topic_0192035902_p143284526385"><a name="dcs-faq-0730040__en-us_topic_0192035902_li14525133819383"></a><a name="en-us_topic_0192035902_li14525133819383"></a>For security purposes, some Redis commands are disabled in DCS. For details about disabled and restricted Redis commands, see <a href="dcs-pd-200312003.html">Command Compatibility</a>.</p>
<ul id="dcs-faq-0730040__en-us_topic_0192035902_ul18525838123819"><li id="dcs-faq-0730040__en-us_topic_0192035902_li6525163893815">The command is incorrect.<p id="dcs-faq-0730040__p1793654714211"><a name="dcs-faq-0730040__en-us_topic_0192035902_li6525163893815"></a><a name="en-us_topic_0192035902_li6525163893815"></a>As shown in the following figure, the error message is returned because the correct command for deleting a key should be <strong id="dcs-faq-0730040__b8911235191915">del</strong>.</p>
<p id="dcs-faq-0730040__p12522551218"><span><img id="dcs-faq-0730040__image58393378210" src="en-us_image_0000001540208017.png"></span></p>
</li><li id="dcs-faq-0730040__li225141316111">A command available in a higher Redis version is run in a lower Redis version.<p id="dcs-faq-0730040__p837784381913"><a name="dcs-faq-0730040__li225141316111"></a><a name="li225141316111"></a>As shown in the following figure, the error message is returned because a stream command (available in Redis 5.0) is run in Redis 3.0.</p>
<p id="dcs-faq-0730040__p667431195"><span><img id="dcs-faq-0730040__image164815412710" src="en-us_image_0000001540447885.png"></span></p>
</li><li id="dcs-faq-0730040__en-us_topic_0192035902_li14525133819383">The command is disabled in DCS.<p id="dcs-faq-0730040__en-us_topic_0192035902_p143284526385"><a name="dcs-faq-0730040__en-us_topic_0192035902_li14525133819383"></a><a name="en-us_topic_0192035902_li14525133819383"></a>For security purposes, some Redis commands are disabled in DCS. For details about disabled and restricted Redis commands, see <a href="dcs-pd-200312003.html">Command Compatibility</a>.</p>
</li><li id="dcs-faq-0730040__en-us_topic_0192035902_li15525238183817">The LUA script fails to be executed.<p id="dcs-faq-0730040__en-us_topic_0192035902_p1181171175114"><a name="dcs-faq-0730040__en-us_topic_0192035902_li15525238183817"></a><a name="en-us_topic_0192035902_li15525238183817"></a>For example, the error message "ERR unknown command 'EVAL'" indicates that your DCS Redis instance is of a lower version that does not support the LUA script. In this case, contact technical support for the instance to be upgraded.</p>
</li><li id="dcs-faq-0730040__en-us_topic_0192035902_li252573843815">The <strong id="dcs-faq-0730040__b72663418711">CLIENT SETNAME</strong> and <strong id="dcs-faq-0730040__b14311834178">CLIENT GETNAME</strong> commands fail to be executed.<p id="dcs-faq-0730040__en-us_topic_0192035902_p12231923532">This is because the DCS Redis instance is of a lower version that does not support these commands. In this case, contact technical support for the instance to be upgraded.</p>
</li></ul>

11
docs/dcs/umn/dcs-faq-0730042.html
View File

@ -1,11 +0,0 @@
<a name="dcs-faq-0730042"></a><a name="dcs-faq-0730042"></a>
<h1 class="topictitle1">Is There a Time Limit on Executing Redis Commands? What Will Happen If a Command Times Out?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730042__en-us_topic_0192035902_p153801628153416">The <span class="keyword" id="dcs-faq-0730042__keyword115192542710">time limit for executing a Redis command</span> is 1 minute. This limit cannot be configured. After the execution of a command times out, your client will be automatically disconnected.</p>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-190921003.html">Redis Commands</a></div>
</div>
</div>

4
docs/dcs/umn/dcs-faq-0730043.html
View File

@ -1,7 +1,7 @@
<a name="dcs-faq-0730043"></a><a name="dcs-faq-0730043"></a>
<h1 class="topictitle1">Can DCS Redis Instances Be Upgraded, for Example, from Redis 3.0 to Redis 4.0 or 5.0?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730043__en-us_topic_0152504023_p8865823410">No. Different Redis versions use different underlying architectures. The Redis version used by a DCS instance cannot be changed once the instance is created. However, you will be informed of any defects or problems found in Redis.</p>
<h1 class="topictitle1">Can DCS Redis Instances Be Upgraded, for Example, from Redis 4.0 to 5.0?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730043__en-us_topic_0152504023_p8865823410">No. Different Redis versions use different underlying architectures. The Redis version used by a DCS instance cannot be changed once the instance is created. For example, you cannot change a DCS Redis 4.0 instance to Redis 5.0. However, you will be informed of any defects or problems found in Redis.</p>
<p id="dcs-faq-0730043__en-us_topic_0152504023_p415618863517">If your service requires the features of higher Redis versions, create a DCS Redis instance of a higher version and then migrate data from the original instance to the new one. For details on how to migrate data, see <a href="dcs-ug-0312035.html">Migrating Data with DCS</a>.</p>
</div>
<div>

2
docs/dcs/umn/dcs-faq-0730045.html
View File

@ -1,6 +1,6 @@
<a name="dcs-faq-0730045"></a><a name="dcs-faq-0730045"></a>
<h1 class="topictitle1">Are Instance Resources Affected During Specification Modification?</h1>
<h1 class="topictitle1">Are Instances Stopped or Restarted During Specification Modification?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730045__en-us_topic_0152504023_p8060118">No. Specification modifications can take place while the instance is running and do not affect any other resources.</p>
</div>
<div>

12
docs/dcs/umn/dcs-faq-0730047.html
View File

@ -2,15 +2,11 @@
<h1 class="topictitle1">Are Services Interrupted During Specification Modification?</h1>
<div id="body1596093494759"><p id="dcs-faq-0730047__p1021363413494">You are advised to change the instance specifications during off-peak hours because specification modification has the following impacts:</p>
<ul id="dcs-faq-0730047__ul6213133444912"><li id="dcs-faq-0730047__li138111124614"><strong id="dcs-faq-0730047__b17334141519424">Impact of instance type changes:</strong><ul id="dcs-faq-0730047__ul201681557194115"><li id="dcs-faq-0730047__li1516816570414">From single-node to master/standby for a DCS Redis 3.0 instance:<p id="dcs-faq-0730047__p11681757204111"><a name="dcs-faq-0730047__li1516816570414"></a><a name="li1516816570414"></a>The instance cannot be connected for several seconds and remains read-only for about 1 minute.</p>
</li><li id="dcs-faq-0730047__li17168195710413">From master/standby to Proxy Cluster for a DCS Redis 3.0 instance:<p id="dcs-faq-0730047__p7168105714120"><a name="dcs-faq-0730047__li17168195710413"></a><a name="li17168195710413"></a>The instance cannot be connected and remains read-only for 5 to 30 minutes.</p>
<ul id="dcs-faq-0730047__ul6213133444912"><li id="dcs-faq-0730047__li16810942145418"><strong id="dcs-faq-0730047__dcs-ug-0326011_b377491373916">Impact of scaling:</strong><ul id="dcs-faq-0730047__dcs-ug-0326011_ul0133828161812"><li id="dcs-faq-0730047__dcs-ug-0326011_li3109163019183">Single-node and master/standby<ul id="dcs-faq-0730047__dcs-ug-0326011_ul1031585795715"><li id="dcs-faq-0730047__dcs-ug-0326011_li66741032162713">A DCS Redis 4.0/5.0/6.0 instance will be disconnected for several seconds and remain read-only for about 1 minute.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li94411853205720">A DCS Redis 3.0 instance will be disconnected and remain read-only for 5 to 30 minutes.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li8701059165713">For scaling up, only the memory of the instance is expanded. The CPU processing capability is not improved.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li123121721584">Data of single-node instances may be lost because they do not support data persistence. After scaling, check whether the data is complete and import data if required.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li111781946192711">Backup records of master/standby instances cannot be used after scaling down.</li></ul>
</li><li id="dcs-faq-0730047__dcs-ug-0326011_li132021415183315">Cluster<ul id="dcs-faq-0730047__dcs-ug-0326011_ul1898119586379"><li id="dcs-faq-0730047__dcs-ug-0326011_li1417512631512">If the shard quantity is not decreased, the instance can always be connected, but the CPU usage will increase, compromising performance by up to 20%, and the latency will increase during data migration.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li126231345133715">During scaling up, new Redis Server nodes are added, and data is automatically balanced to the new nodes.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li77729516162">Nodes will be deleted if the shard quantity decreases. To prevent disconnection, ensure that the deleted nodes are not directly referenced in your application.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li6114126161817">Ensure that the used memory of each node is less than 70% of the maximum memory per node of the new flavor. Otherwise, you cannot perform the scale-in.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li64187064519">If the memory becomes full during scaling due to a large amount of data being written, scaling will fail. Modify specifications during off-peak hours.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li1963862124517">Scaling involves data migration. The latency for accessing the key being migrated increases. For a Redis Cluster instance, ensure that the client can properly process the <strong id="dcs-faq-0730047__dcs-ug-0326011_b151867513115">MOVED</strong> and <strong id="dcs-faq-0730047__dcs-ug-0326011_b6644135219116">ASK</strong> commands. Otherwise, requests will fail.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li75521747164618">Before scaling, perform cache analysis to ensure that no big keys (≥ 512 MB) exist in the instance. Otherwise, scaling may fail.</li><li id="dcs-faq-0730047__dcs-ug-0326011_li766133173811">Backup records created before scaling cannot be restored.</li></ul>
</li></ul>
</li><li id="dcs-faq-0730047__li132138341492"><strong id="dcs-faq-0730047__b7884113024319">Impact of capacity expansion and reduction:</strong><ul id="dcs-faq-0730047__ul0133828161812"><li id="dcs-faq-0730047__li3109163019183">Single-node and master/standby<p id="dcs-faq-0730047__p121453416499"><a name="dcs-faq-0730047__li3109163019183"></a><a name="li3109163019183"></a>The DCS Redis 3.0, 4.0, or 5.0 instance cannot be connected for several seconds and remains read-only for about 1 minute.</p>
<p id="dcs-faq-0730047__p221416346493">For capacity expansion, only the memory of the instance is expanded. The CPU processing capability is not improved.</p>
<p id="dcs-faq-0730047__p9214334134920">Data of single-node instances may not be retained because they do not support data persistence. After the scaling, check whether the data is complete and import data if required.</p>
</li><li id="dcs-faq-0730047__li1121415340498">Proxy Cluster<p id="dcs-faq-0730047__p12141034164916"><a name="dcs-faq-0730047__li1121415340498"></a><a name="li1121415340498"></a>The instance can be connected, but the CPU will be occupied and the latency will increase during data migration. During capacity expansion, new Redis Server nodes are added, and data is automatically balanced to the new nodes.</p>
</li><li id="dcs-faq-0730047__li123541562345">Redis Cluster<p id="dcs-faq-0730047__p10399114233413"><a name="dcs-faq-0730047__li123541562345"></a><a name="li123541562345"></a>The instance can be connected, but the CPU usage and latency will increase during data migration. During capacity expansion, new Redis Server nodes are added, and data is automatically balanced to the new nodes.</p>
</li><li id="dcs-faq-0730047__li7563144612278">Backup records created before the capacity change cannot be restored.</li></ul>
</li></ul>
<ul id="dcs-faq-0730047__ul2889344155714"><li id="dcs-faq-0730047__li1332219598417"><strong id="dcs-faq-0730047__dcs-ug-0326011_b6842205425117">Notes on changing the number of replicas of a DCS Redis 4.0 or 5.0 instance:</strong><p id="dcs-faq-0730047__dcs-ug-0326011_p63371629113112">Deleting replicas interrupts connections. If your application cannot reconnect to Redis or handle exceptions, you need to restart the application after scaling.</p>
</li></ul>
</div>
<div>

2
docs/dcs/umn/dcs-faq-0730054.html
View File

@ -3,7 +3,7 @@
<h1 class="topictitle1">Can I Export Backup Data of DCS Redis Instances to RDB Files Using the Console?</h1>
<div id="body1596093777162"><ul id="dcs-faq-0730054__ul529275204312"><li id="dcs-faq-0730054__li8293125224314">Redis 3.0<p id="dcs-faq-0730054__p16229175411211"><a name="dcs-faq-0730054__li8293125224314"></a><a name="li8293125224314"></a>No. On the console, backup data of a DCS Redis 3.0 instance can be exported only to AOF files. To export data to RDB files, run the following command in redis-cli:</p>
<p id="dcs-faq-0730054__p104694614429"><strong id="dcs-faq-0730054__b8468467424">redis-cli -h <em id="dcs-faq-0730054__i1551113114572">{redis_address}</em> -p 6379 [-a <em id="dcs-faq-0730054__i1744435711585">password</em>] --rdb {output.rdb}</strong></p>
</li><li id="dcs-faq-0730054__li711514111449">Redis 4.0 and 5.0<p id="dcs-faq-0730054__p1138991224411"><a name="dcs-faq-0730054__li711514111449"></a><a name="li711514111449"></a>Yes. Backup data of a DCS Redis 4.0 or 5.0 instance is exported from the console to RDB files. You cannot use redis-cli to export such data to RDB files.</p>
</li><li id="dcs-faq-0730054__li711514111449">Redis 4.0/5.0/6.0<p id="dcs-faq-0730054__p1138991224411"><a name="dcs-faq-0730054__li711514111449"></a><a name="li711514111449"></a>Yes. DCS Redis 4.0/5.0/6.0 instances support AOF and RDB persistence. You can back up data to RDB and AOF files on the console and download the files.</p>
</li></ul>
</div>
<div>

12
docs/dcs/umn/dcs-faq-0730057.html
View File

@ -1,12 +0,0 @@
<a name="dcs-faq-0730057"></a><a name="dcs-faq-0730057"></a>
<h1 class="topictitle1">Does DCS Support Data Persistence?</h1>
<div id="body1596093777162"><div class="p" id="dcs-faq-0730057__p29711441144117">DCS Redis instances:<ul id="dcs-faq-0730057__en-us_topic_0152504022_ul8386756113825"><li id="dcs-faq-0730057__en-us_topic_0152504022_li40228198113825">Single-node: Not supported</li><li id="dcs-faq-0730057__en-us_topic_0152504022_li43901409113836">Master/Standby and cluster: Supported</li></ul>
</div>
</div>
<div>
<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="dcs-faq-0326024.html">Data Backup, Export, and Migration</a></div>
</div>
</div>

Some files were not shown because too many files have changed in this diff Show More