k8s学习一：centos7单机安装k8s
初始安装
- yum install -y etcd kubernetes
- vim /etc/sysconfig/docker
# 内容改为如下
OPTIONS='--selinux-enabled=false --insecure-registry gcr.io'- vim /etc/kubernetes/apiserver 去掉–admission-control中的ServiceAccount
- systemctl start etcd.service
- systemctl start docker
- systemctl start kube-apiserver.service
- systemctl start kube-controller-manager.service
- systemctl start kube-scheduler.service
- systemctl start kubelet.service
- systemctl start kube-proxy.service
- mkdir /data
- vim mysql-rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
name: mysql
spec:
replicas: 1
selector:
app: mysql
template:
metadata:
labels:
app: mysql
spec:
containers:
- name: mysql
image: mysql
ports:
- containerPort: 3306
env:
- name: MYSQL_ROOT_PASSWORD
value: "123456"- kubectl create -f mysql-rc.yaml
- kubectl get rc
NAME DESIRED CURRENT READY AGE
mysql 1 1 0 12m- kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-zqgck 0/1 ContainerCreating 0 13m发现status一直处于ContainerCreating状态！！！
- kubectl describe pod mysql （该命令用于排查上面状态一直卡在ContainerCreating的情况）
Name: mysql-zqgck
Namespace: default
Node: 127.0.0.1/127.0.0.1
Start Time: Tue, 05 Jun 2018 10:25:31 -0400
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:
Environment Variables:
MYSQL_ROOT_PASSWORD: 123456
Conditions:
Type Status
Initialized True
Ready False
PodScheduled True
No volumes.
QoS Class: BestEffort
Tolerations:
Events:
FirstSeen LastSeen Count From SubObjectPath Type Reason Message
--------- -------- ----- ---- ------------- -------- ------ -------
14m 14m 1 {default-scheduler } Normal Scheduled Successfully assigned mysql-zqgck to 127.0.0.1
14m 3m 7 {kubelet 127.0.0.1} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ErrImagePull: "image pull failed for registry.access.redhat.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)"
14m 4s 60 {kubelet 127.0.0.1} Warning FailedSync Error syncing pod, skipping: failed to "StartContainer" for "POD" with ImagePullBackOff: "Back-off pulling image \"registry.access.redhat.com/rhel7/pod-infrastructure:latest\""
- 发现错误open /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt: no such file or directory，网上找的方法：
- 运行 ll /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt 发现其指向/etc/rhsm/ca/redhat-uep.pem
- 查看发现没有/etc/rhsm/ca/redhat-uep.pem 文件
- 运行 yum install *rhsm* 发现已安装问题没解决。。。。继续
- 运行yum search rhsm
================================================ N/S matched: rhsm ================================================
python-rhsm.x86_64 : A Python library to communicate with a Red Hat Unified Entitlement Platform
python-rhsm-certificates.x86_64 : Certificates required to communicate with a Red Hat Unified Entitlement Platform
subscription-manager-rhsm.x86_64 : A Python library to communicate with a Red Hat Unified Entitlement Platform
subscription-manager-rhsm-certificates.x86_64 : Certificates required to communicate with a Red Hat Unified
: Entitlement Platform
- 发现python-rhsm-certificates.x86_64比较像，则运行yum install python-rhsm-certificates
软件包 python-rhsm-certificates-1.19.10-1.el7_4.x86_64 被已安装的 subscription-manager-rhsm-certificates-1.20.11-1.el7.centos.x86_64 取代
无须任何处理无语，已被取代，现在考虑是不是版本问题。。。。。网上找。。。。
- 运行wget http://mirror.centos.org/centos/7/os/x86_64/Packages/python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm 手动下载
- chmod +x python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm
- 运行 rpm2cpio python-rhsm-certificates-1.19.10-1.el7_4.x86_64.rpm | cpio -iv --to-stdout /etc/rhsm/ca/redhat-uep.pem | tee /etc/rhsm/ca/redhat-uep.pem发现ll /etc/docker/certs.d/registry.access.redhat.com/redhat-ca.crt已经指向正确了
- kubectl delete -f mysql-rc.yaml
- kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-zqgck 0/1 Terminating 0 38m尼玛悲剧，发现一直卡在Terminating状态。。。。继续问度娘。。。
- 运行systemctl status kube-apiserver.service
- kubectl get pods
No resources found.好了，终于删掉了,继续重新创建。。。。
- kubectl create -f mysql-rc.yaml
- kubectl get rc
NAME DESIRED CURRENT READY AGE
mysql 1 1 1 1m
- kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-gtcj4 1/1 Running 0 12s终于成功了。。。。Running了。。。。
- docker ps查看运行的容器：docker ps | grep mysql
2ecf0982d281 mysql "docker-entrypoint..." 2 minutes ago Up 2 minutes k8s_mysql.f6601b53_mysql-gtcj4_default_970ff879-68d2-11e8-85b7-001c42f5e75e_b1252eaf
5acb60408a8c registry.access.redhat.com/rhel7/pod-infrastructure:latest "/usr/bin/pod" 2 minutes ago Up 2 minutes k8s_POD.1d520ba5_mysql-gtcj4_default_970ff879-68d2-11e8-85b7-001c42f5e75e_6b6bbff9- vim mysql-svc.yaml 创建service文件
apiVersion: v1
kind: Service
metadata:
name: mysql
spec:
ports:
- port: 3306
selector:
app: mysql- kubectl create -f mysql-svc.yaml 创建service
- kubectl get svc
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes 10.254.0.1 <none> 443/TCP 1h
mysql 10.254.65.184 <none> 3306/TCP 14s这个还顺利，直接就ok了
- docker ps| grep mysql即可看到运行的进程
第二天服务器重启后
- systemctl status etcd.service
etcd.service - Etcd Server
Loaded: loaded (/usr/lib/systemd/system/etcd.service; disabled; vendor preset: disabled)
Active: inactive (dead)悲剧，没有设置自启动。。。。重启服务。。。。
- 启动服务
- systemctl start etcd.service
- systemctl start docker
- systemctl start kube-apiserver.service
- systemctl start kube-controller-manager.service
- systemctl start kube-scheduler.service
- systemctl start kubelet.service
- systemctl start kube-proxy.service - kubectl get pods
[root@centos-linux ~]# kubectl get pods
NAME READY STATUS RESTARTS AGE
mysql-gtcj4 1/1 Running 1 10h服务启动后，发现mysql已经启动了