29.B站薪享宏福笔记——第十一章（3）固定IP地址

11 B站薪享宏福笔记——第十一章

11.4 固定 IP 地址至 Pod

　　　　　　　　　　　　　　　　　—— 满足特殊需求的地址分配

11.4.1 网络插件配置

修改配置文件 /etc/cni/net.d/10-calico.conflist ，将 ipam 类型修改为 calico-ipam（启动 calico 的 ip 管理器，实现单个 pod 地址的固定化分配）

[root@k8s-master01 11.4]# cat /etc/cni/net.d/10-calico.conflist 
{
  "name": "k8s-pod-network",
  "cniVersion": "0.3.1",
  "plugins": [
    {
      "type": "calico",
      "log_level": "info",
      "log_file_path": "/var/log/calico/cni/cni.log",
      "datastore_type": "kubernetes",
      "nodename": "k8s-master01",
      "mtu": 0,
      "ipam": {
          "type": "calico-ipam"
      },
      "policy": {
          "type": "k8s"
      },
      "kubernetes": {
          "kubeconfig": "/etc/cni/net.d/calico-kubeconfig"
      }
    },
    {
      "type": "portmap",
      "snat": true,
      "capabilities": {"portMappings": true}
    },
    {
      "type": "bandwidth",
      "capabilities": {"bandwidth": true}
    }
  ]
}

11.4.2 固定 IP 测试

[root@k8s-master01 11.4]# cat ip_pod.yaml 
apiVersion: v1
kind: Pod
metadata:
 labels:
   app: myapp
 annotations:
   "cni.projectcalico.org/ipAddrs": "[\"10.244.140.67\"]"
 name: myapp-ip
 namespace: default
spec:
 containers:
 - image: myapp:v1.0
   imagePullPolicy: IfNotPresent
   name: myapp

3.元数据：标签：key: value、描述信息：key 名: 固定 IP 值、Pod 名、Pod 所在名称空间

注意：Pod 的 IP 必须在集群中没有使用，已存在的没办法竞争 IP 地址

[root@k8s-master01 11.4]# kubectl apply -f ip_pod.yaml 
pod/myapp-ip created
[root@k8s-master01 11.4]# kubectl get pod -o wide
NAME       READY   STATUS    RESTARTS   AGE   IP              NODE         NOMINATED NODE   READINESS GATES
myapp-ip   1/1     Running   0          6s    10.244.140.67   k8s-node02   <none>           <none>
[root@k8s-master01 11.4]# kubectl delete -f ip_pod.yaml 
pod "myapp-ip" deleted
[root@k8s-master01 11.4]# kubectl apply -f ip_pod.yaml 
pod/myapp-ip created
[root@k8s-master01 11.4]# kubectl get pod -o wide
NAME       READY   STATUS    RESTARTS   AGE   IP              NODE         NOMINATED NODE   READINESS GATES
myapp-ip   1/1     Running   0          9s    10.244.140.67   k8s-node02   <none>           <none>

11.4.3 固定 IP 无法竞争

# 仅与上面的 Pod 名称不同，IP 地址是相同的
[root@k8s-master01 11.4]# cat ip2_pod.yaml 
apiVersion: v1
kind: Pod
metadata:
 labels:
   app: myapp
 annotations:
   "cni.projectcalico.org/ipAddrs": "[\"10.244.140.67\"]"
 name: myapp-ip-2
 namespace: default
spec:
 containers:
 - image: myapp:v1.0
   imagePullPolicy: IfNotPresent
   name: myapp

# 再次创建相同 IP 地址的 Pod ,无法创建成功，显示 IP 地址已存在
[root@k8s-master01 11.4]# kubectl get pod -o wide
NAME       READY   STATUS    RESTARTS   AGE   IP              NODE         NOMINATED NODE   READINESS GATES
myapp-ip   1/1     Running   0          14m   10.244.140.67   k8s-node02   <none>           <none>
[root@k8s-master01 11.4]# kubectl apply -f ip2_pod.yaml 
pod/myapp-ip-2 created
[root@k8s-master01 11.4]# kubectl get pod -o wide
NAME         READY   STATUS              RESTARTS   AGE   IP              NODE         NOMINATED NODE   READINESS GATES
myapp-ip     1/1     Running             0          14m   10.244.140.67   k8s-node02   <none>           <none>
myapp-ip-2   0/1     ContainerCreating   0          9s    <none>          k8s-node01   <none>           <none>
[root@k8s-master01 11.4]# kubectl describe pod myapp-ip-2
.........
Events:
  Type     Reason                  Age                From               Message
  ----     ------                  ----               ----               -------
  Normal   Scheduled               36s                default-scheduler  Successfully assigned default/myapp-ip-2 to k8s-node01
  Warning  FailedCreatePodSandBox  30s                kubelet            Failed to create pod sandbox: rpc error: code = Unknown desc = failed to set up sandbox container "88e65cd7870bff9474496d0b7526d1ab98a222ab9809cc4cf19d0f3d3c2b7328" network for pod "myapp-ip-2": networkPlugin cni failed to set up pod "myapp-ip-2_default" network: plugin type="calico" failed (add): error getting IP from IPAM: resource already exists: 10.244.140.67

11.4.4 总结

固定 IP 在使用过程中可能会遇到 IP 没有释放等问题导致 Pod 启动失败，原因可能是 Pod 被删除后，使用的 IP 地址还未被释放，所以需要使用命令对地址池中的 IP 进行释放，才能够被 Pod 重新使用

calicoctl ipam release --ip 10.244.140.67

# 安装 calicoctl 客户端工具的方法
# 第一种，下载后 apply 
[root@k8s-master01 11.4]# wget https://docs.projectcalico.org/manifests/calicoctl.yaml
--2025-07-31 13:37:29--  https://docs.projectcalico.org/manifests/calicoctl.yaml
Resolving docs.projectcalico.org (docs.projectcalico.org)... 52.74.6.109, 13.215.239.219, 2406:da18:b3d:e201::258, ...
Connecting to docs.projectcalico.org (docs.projectcalico.org)|52.74.6.109|:443... connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: https://calico-v3-25.netlify.app/archive/v3.25/manifests/calicoctl.yaml [following]
--2025-07-31 13:37:31--  https://calico-v3-25.netlify.app/archive/v3.25/manifests/calicoctl.yaml
Resolving calico-v3-25.netlify.app (calico-v3-25.netlify.app)... 52.74.6.109, 13.215.239.219, 2406:da18:b3d:e201::259, ...
Connecting to calico-v3-25.netlify.app (calico-v3-25.netlify.app)|52.74.6.109|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 2019 (2.0K) [text/yaml]
Saving to: ‘calicoctl.yaml’

calicoctl.yaml                                              100%[========================================================================================================================================>]   1.97K  --.-KB/s    in 0s

# 第二种，直接 apply 网址的 yaml 文件
[root@k8s-master01 11.4]# kubectl apply -f https://docs.projectcalico.org/manifests/calicoctl.yaml
serviceaccount/calicoctl created
pod/calicoctl created
clusterrole.rbac.authorization.k8s.io/calicoctl created
clusterrolebinding.rbac.authorization.k8s.io/calicoctl created
[root@k8s-master01 11.4]# kubectl get pod -n kube-system |grep calicoctl
calicoctl                                  1/1     Running   0                10m

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posted on 2025-07-24 15:32 马俊南阅读(64) 评论(0) 收藏举报