创建Deployment后，无法创建Pod问题处理

Posted 2022-06-28 键客李大白

问题描述

我在二进制安装的kubernetes集群部署Ingress服务过程中，使用yaml文件apply创建对应资源Deployment过程中，一直无法看到Pod被创建出来。

[root@two-master Install]# kubectl apply -f ingress-nginx-controller.yaml
deployment.apps/default-http-backend created
service/default-http-backend created
serviceaccount/nginx-ingress-serviceaccount created
clusterrole.rbac.authorization.k8s.io/nginx-ingress-clusterrole created
role.rbac.authorization.k8s.io/nginx-ingress-role created
clusterrolebinding.rbac.authorization.k8s.io/nginx-ingress-clusterrole-nisa-binding created
deployment.apps/nginx-ingress-controller created

[root@two-master Install]# kubectl -n kube-system get  pods

处理过程

查看Deployment的详细信息

[root@two-master Install]# kubectl -n kube-system describe  deployments.apps nginx-ingress-controller

没有得到有价值的信息。

查看kube-controller-manager服务状态

[root@two-master Install]# systemctl status kube-controller-manager.service
......
6月 25 18:54:54 two-master kube-controller-manager[759]: E0625 18:54:54.563462     759 leaderelection.go:325] error retrieving resource lo...nager)

可以看出kube-controller-manager服务状态确实有问题。

• 继续查看kube-controller-manager服务详细的报错信息

[root@two-master Install]# systemctl status kube-controller-manager.service    > kube-controller.log
[root@two-master Install]# vim + kube-controller.log    #导出到日志文件中，方便查看
known reason (get leases.coordination.k8s.io kube-controller-manager)
6月 25 19:10:25 two-master kube-controller-manager[759]: E0625 19:10:25.198986     759 leaderelection.go:325] 
error retrieving resource lock kube-system/kube-controller-manager: 
the server rejected our request for an unknown reason (get leases.coordination.k8s.io kube-controller-manager)

得出有效的报错信息：

known reason (get leases.coordination.k8s.io kube-controller-manager)
6月 25 19:10:25 two-master kube-controller-manager[759]: E0625 19:10:25.198986     759 leaderelection.go:325] error retrieving resource lock kube-system/kube-controller-manager: the server rejected our request for an unknown reason (get leases.coordination.k8s.io kube-controller-manager)

百度翻译下：

意思：

 检索资源锁kube-system/kube-controller-manager出错：服务器因未知原因拒绝了我们的请求（get leaves.coordination.k8s.io kube控制器管理器）

查看etcd集群状态和告警信息

 复制报错信息到百度搜索，有说是etcd集群问题，于是查看我的etcd是否正常。

我的kubernetes就一个master、2个node。

• 查看etcd状态是否正常

[root@two-master Install]# etcdctl endpoint health  --endpoints=https://192.168.2.70:2379 \\
> --write-out=table  \\
> --cacert=/etc/kubernetes/pki/etcd/ca.pem  \\
> --cert=/etc/kubernetes/pki/etcd/etcd.pem \\
> --key=/etc/kubernetes/pki/etcd/etcd-key.pem
+---------------------------+--------+------------+-------+
|         ENDPOINT          | HEALTH |    TOOK    | ERROR |
+---------------------------+--------+------------+-------+
| https://192.168.2.70:2379 |   true | 4.965087ms |       |
+---------------------------+--------+------------+-------+   #正常，没有报错

• 查看etcd告警信息

[root@two-master Install]# etcdctl --endpoints  192.168.2.70:2379  alarm list \\
> --cacert=/etc/kubernetes/pki/etcd/ca.pem \\
> --cert=/etc/kubernetes/pki/etcd/etcd.pem  \\
> --key=/etc/kubernetes/pki/etcd/etcd-key.pem

无告警信息，etcd正常，问题的原因还没找到。

重启kube-controller-manager服务

试试重启大法。

                                              

[root@two-master ~]# systemctl restart  kube-controller-manager.service 
[root@two-master ~]# systemctl status kube-controller-manager.service

服务还是异常。

查看资源锁

leases是轻量级的资源锁，用于代替老版本的configmap和endpoints，我们使用kubectl get lease kube-controller-manager -n kube-system -o yaml命令可以看到以下的yaml。

$ kubectl get lease kube-controller-manager -n kube-system -o yaml
apiVersion: coordination.k8s.io/v1
kind: Lease
metadata:
  creationTimestamp: "2022-06-08T07:52:17Z"
  managedFields:
  - apiVersion: coordination.k8s.io/v1
    fieldsType: FieldsV1
    fieldsV1:
      f:spec:
        f:acquireTime: 
        f:holderIdentity: 
        f:leaseDurationSeconds: 
        f:leaseTransitions: 
        f:renewTime: 
    manager: kube-controller-manager
    operation: Update
    time: "2022-06-08T07:52:17Z"
  name: kube-controller-manager
  namespace: kube-system
  resourceVersion: "977951"
  uid: 758e5b3d-422f-4254-9839-3581f532b7e5
spec:
  acquireTime: "2022-06-24T02:08:11.905250Z"
  holderIdentity: two-master_f1deccfa-7a21-4b6c-97b6-611eaaff083c
  leaseDurationSeconds: 15
  leaseTransitions: 7
  renewTime: "2022-06-24T03:01:34.576989Z"

该资源记录了哪个实例持有了该资源，更新任期的时间，获得锁的时间等等信息。

• LeaseDuration：持有锁的时间，表示该任期的持续时间，在这时间内其他LeaderElector客户端无法获取leader职位，即便当前的leader无法正常工作。
• RenewDeadline：更新锁的持有时间，该字段仅对leader生效，用于刷新leaseDuration延续其任期的时间，放弃之前重试刷新领导的时间。RenewDeadline必须小于LeaseDuration。
• RetryPeriod：重试时间，每个LeaderElector客户端的重试时间，用于尝试成为leader。
• Callbacks：每次成为leader或者失去leader时回调函数。

请求资源锁

[root@two-master ~]# curl -X GET   https://192.168.2.70:6443/apis/coordination.k8s.io/v1/namespaces/kube-system/leases/kube-controller-manager -k

  "kind": "Status",
  "apiVersion": "v1",
  "metadata": 
    
  ,
  "status": "Failure",
  "message": "Unauthorized",
  "reason": "Unauthorized",
  "code": 401    #返回401异常，
[root@two-master ~]#

补充：

后来排查发现在/etc/kubernetes/kube-controller-manager.conf文件中多添加了到kube-apiserver的参数，删除该参数重启服务后正常了。