Application Scenarios

In Cloud Native Network 2.0, static public IP addresses (EIPs) can be assigned to StatefulSets or pods created directly.

Constraints

You can configure a static EIP for a pod only in CCE Turbo clusters of the following versions:
- v1.19: v1.19.16-r20 or later
- v1.21: v1.21.10-r0 or later
- v1.23: v1.23.8-r0 or later
- v1.25: v1.25.3-r0 or later
- v1.25 or later
The static EIP function must be enabled together with the function of automatically allocating an EIP for a pod. For details, see Configuring an EIP for a Pod.
Only StatefulSet pods or pods created directly can be bound with static EIPs. Deployments, DaemonSets, and other types of workloads cannot be bound with static EIPs.
After a static EIP is allocated, the EIP attributes cannot be modified through the pod within the EIP lifecycle (before the EIP expires or it is still being used by the pod).
Do not configure a static EIP for services that do not have specific requirements on pod EIPs. Otherwise, the pod rebuilding takes a longer time.

Configuring a Static EIP for a Pod

When creating a pod to be bound with a static IP address, configure the EIP annotation. Then, an EIP will be automatically allocated and bound to the pod.

The following uses a StatefulSet named nginx as an example. For details about annotations, see Table 1.

For an automatically allocated EIP with a dedicated bandwidth when you create a StatefulSet, you do not need to specify the bandwidth ID. The following shows an example:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx
spec:
  serviceName: nginx
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
      annotations:
        yangtse.io/static-eip: 'true'   # Static EIP bound to the pod
        yangtse.io/static-eip-expire-no-cascading: 'false'   # Deleting the EIP with the associated workload
        yangtse.io/static-eip-expire-duration: 5m   # Interval for reclaiming expired EIPs
        yangtse.io/pod-with-eip: 'true'   # An EIP will be automatically allocated when the pod is created.
        yangtse.io/eip-bandwidth-size: '5'    # EIP bandwidth
        yangtse.io/eip-network-type: 5_bgp    # EIP type
        yangtse.io/eip-charge-mode: bandwidth    # EIP billing mode
    spec:
      containers:
        - name: container-0
          image: nginx:alpine
          resources:
            limits:
              cpu: 100m
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 200Mi
      imagePullSecrets:
        - name: default-secret

For an automatically allocated EIP with a shared bandwidth when you create a StatefulSet, you are required to specify the bandwidth ID. The following shows an example:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx
spec:
  serviceName: nginx
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
      annotations:
        yangtse.io/static-eip: 'true'   # Static EIP bound to the pod
        yangtse.io/pod-with-eip: 'true'   # An EIP will be automatically allocated when the pod is created.
        yangtse.io/eip-network-type: 5_bgp    # EIP type
        yangtse.io/eip-bandwidth-id: <eip_bandwidth_id>    # Shared bandwidth ID of the EIP
    spec:
      containers:
        - name: container-0
          image: nginx:alpine
          resources:
            limits:
              cpu: 100m
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 200Mi
      imagePullSecrets:
        - name: default-secret

**Table 1** Annotations of the pod's static EIP
Annotation	Mandatory	Default Value	Description	Value Range
yangtse.io/static-eip	Yes	false	Specifies whether to enable the static EIP of a pod. This function is supported only for StatefulSet pods or pods without ownerReferences. This function is disabled by default.	false or true
yangtse.io/static-eip-expire-duration	No	5m	Specifies the interval for reclaiming the expired static EIP after the pod with a static EIP is deleted.	The time format is Go time type, for example, 1h30m and 5m. For details, see Go time type.
yangtse.io/static-eip-expire-no-cascading	No	false	Specifies whether to disable cascading reclamation of StatefulSet workloads. The default value is false, indicating that the corresponding static EIP will be deleted with the StatefulSet workload. If you want to retain the static EIP for a new StatefulSet with the same name during the interval for reclaiming the expired EIP, set the value to true.	false or true

**Table 2** Annotations of an EIP with a dedicated bandwidth
Annotation	Mandatory	Default Value	Description	Value Range
yangtse.io/pod-with-eip	Yes	false	Whether to allocate an EIP with a pod and bind the EIP to the pod	false or true
yangtse.io/eip-bandwidth-size	No	5	Bandwidth, in Mbit/s	The value range varies depending on the region and bandwidth billing mode. For details, see the EIP console.
yangtse.io/eip-network-type	No	5_bgp	EIP type	The type varies depending on the region. For details, see on the EIP console.
yangtse.io/eip-charge-mode	No	None	Billed by traffic or bandwidth You are advised to configure this parameter. If this parameter is left blank, no billing mode is specified. In this case, the default value of the EIP API in the region is used.	bandwidth: billed by bandwidth traffic: billed by traffic
yangtse.io/eip-bandwidth-name	No	Pod name	Bandwidth name	Enter 1 to 64 characters. Only letters, digits, hyphens (-), underscores (_), and periods (.) are allowed. Minimum length: 1 character Maximum length: 64 characters

**Table 3** Annotations of an EIP with a shared bandwidth
Annotation	Mandatory	Default Value	Description	Value Range
yangtse.io/pod-with-eip	Yes	false	Whether to allocate an EIP with a pod and bind the EIP to the pod	false or true
yangtse.io/eip-network-type	No	5_bgp	EIP type	5_bgp The specific type varies with regions. For details, see the EIP console.
yangtse.io/eip-bandwidth-id	Mandatory when a shared bandwidth is used	None	ID of an existing bandwidth If this parameter is not specified, the EIP with a dedicated bandwidth is used by default. For details about how to configure parameters for an EIP with a dedicated bandwidth, see Table 1. Only the yangtse.io/eip-network-type field can be specified concurrently, and this field is optional.	None

Deleting a Static EIP

After a pod is deleted, if another pod with the same name is created before the static EIP expires, the EIP can still be used. The static EIP is deleted only if there is no new pod with the name the same as that of the deleted pod before the EIP expires, or the function of deleting the EIP with the associated StatefulSet is enabled and the StatefulSet is deleted.