:original_name: ddm_01_0007.html

.. _ddm_01_0007:

Regions and AZs
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Concepts
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The combination of a region and an availability zone (AZ) identifies the location of a data center. You can create resources in a specific AZ in a region.

-  A region is a geographic area where physical data centers are located. Each region is completely independent, improving fault tolerance and stability. After a resource is created, its region cannot be changed.
-  An AZ is a physical location using independent power supplies and networks. Faults in an AZ do not affect other AZs. A region can contain multiple AZs, which are physically isolated but interconnected through internal networks. This ensures the independence of AZs and provides low-cost and low-latency network connections.

shows the relationship between regions and AZs.

Selecting a Region
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You are advised to select a region close to you or your target users. This reduces network latency and improves access rate.

Selecting an AZ
---------------

When determining whether to deploy resources in the same AZ, consider your applications' requirements on disaster recovery (DR) and network latency.

-  For high DR capability, deploy resources in different AZs in the same region.
-  For low network latency, deploy resources in the same AZ.