今天在學習kubernetes的時候啓動了一個msyql服務，運行命令
[root@liuxuchong kubernetes]# kubectl create -f mysql-rc.yaml
replicationcontroller "mysql" created
[root@liuxuchong kubernetes]# kubectl get all
NAME DESIRED CURRENT READY AGE
rc/mysql 1 1 0 6m
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
svc/kubernetes 10.254.0.1 <none> 443/TCP 10m
NAME READY STATUS RESTARTS AGE
po/mysql-f7df5 0/1 ContainerCreating 0 6m
可以看到rc沒有ready，並且pod一直顯示ContainerCreating
顯示pod詳細信息
[root@liuxuchong ca]# kubectl describe pod mysql-f7df5
Name: mysql-f7df5
Namespace: default
Node: 127.0.0.1/127.0.0.1
Start Time: Wed, 15 May 2019 11:56:38 +0800
Labels: app=mysql
Status: Pending
IP:
Controllers: ReplicationController/mysql
Containers:
mysql:
Container ID:
Image: mysql
Image ID:
Port: 3306/TCP
State: Waiting
Reason: ContainerCreating
Ready: False
Restart Count: 0
Volume Mounts: <none>
Environment Variables:
MYSQL_ROOT_PASSWORD: 123456
Conditions:
Type Status
Initialized True
Ready False
PodScheduled True
No volumes.
QoS Class: BestEffort
Tolerations: <none>
Events:
FirstSeen LastSeen Count From SubObjectPath Type Reason Message
--------- -------- ----- ---- ------------- -------- ------ -------
5m 5m 1 {default-scheduler } Normal Scheduled Successfully assigned mysql-f7df5 to 127.0.0.1
5m 2m 5 {kubelet 127.0.0.1} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull faileredhat.com/rhel7/pod-infrastructure:latest, this may be because there are no credentials on this request. details: (open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory)"
4m 5s 19 {kubelet 127.0.0.1} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redastructure:latest\""
看到了倆個警告，第一個是說拉取鏡像請求失敗，括號裏的意思是沒有這個目錄，手動查了一遍發現有這個目錄，網上說安裝一下rhsm，yum install rhsm -y，發現問題還是沒有解決，於是想到拉取鏡像需要訪問外網，阿里雲的機器不能訪問外網，於是從國外的服務器拉取了鏡像。
用命令journalctl -u kubelet -f查看一下日誌
[root@liuxuchong kubernetes]# journalctl -u kubelet -f
-- Logs begin at Tue 2018-04-10 03:20:48 CST. --
May 15 12:02:25 liuxuchong kubelet[28192]: E0515 12:02:25.614469 28192 docker_manager.go:2159] Failed to create pod infra container: ImagePullBackOff; Skipping pod "mysql-f7df5_default(70ce53f4-76c5-11e9-963f-00163e324a1f)": Back-off pulling image "registry.access.redhat.com/rhel7/pod-infrastructure:latest"
May 15 12:02:25 liuxuchong kubelet[28192]: E0515 12:02:25.614942 28192 pod_workers.go:184] Error syncing pod 70ce53f4-76c5-11e9-963f-00163e324a1f, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""果斷拉取（可以訪問外網的服務器)
docker pull registry.access.redhat.com/rhel7/pod-infrastructure:latest
然後上傳到dockerhub上，上傳過程就不詳細說了，不會自行百度，然後在本地機器上拉取該鏡像，改一下名字
命名爲registry.access.redhat.com/rhel7/pod-infrastructure:latest
最後刪除原來的rc和pod
[root@liuxuchong ca]# kubectl get all
NAME DESIRED CURRENT READY AGE
rc/mysql 1 1 0 6m
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
svc/kubernetes 10.254.0.1 <none> 443/TCP 10m
NAME READY STATUS RESTARTS AGE
po/mysql-f7df5 0/1 ContainerCreating 0 6m
[root@liuxuchong ca]# kubectl delete rc mysql
replicationcontroller "mysql" deleted
[root@liuxuchong ca]# kubectl delete pod mysql-f7df5
pod "mysql-f7df5" deleted重新創建
[root@liuxuchong kubernetes]# kubectl create -f mysql-rc.yaml
replicationcontroller "mysql" created
[root@liuxuchong kubernetes]# kubectl get rc
NAME DESIRED CURRENT READY AGE
mysql 1 1 1 7s
[root@liuxuchong kubernetes]# kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-r4kxq 1/1 Running 0 12spod的狀態終於變成了Running