搭建docker私有仓库，建立k8s集群

服务器IP角色分布

192.168.5.2  etcd server
192.168.5.2  kubernetes master
192.168.5.3  kubernetes node
192.168.5.4  kubernetes node

确认环境

centos7
确认liunx内核版本  uname -a
yum update

systemctl start firewalld.service#启动firewall
systemctl stop firewalld.service#停止firewall
systemctl disable firewalld.service#禁止firewall开机启动


yum -y install ntp
systemctl start ntpd
systemctl enable ntpd

软件安装

etcd
yum install etcd -y

master
yum install kubernetes-master -y

node
yum install kubernetes-node flannel docker -y

各组件用途

kube master
    kube-apiserver
    kube-scheduer
    kube-controller-manager

etcd配置启动

egrep -v “^#” /etc/etcd/etcd.conf
ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.5.2:2379"


[root@Control k8s]# cat etcd_start.sh
systemctl enable etcd
systemctl start etcd

ss -antl 检查2379是否成功

master服务配置启动

[root@Control k8s]# egrep -v '^#' /etc/kubernetes/apiserver | grep -v '^$'
KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
KUBE_ETCD_SERVERS="--etcd-servers=http://192.168.5.2:2379"
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"
KUBE_API_ARGS=""

[root@Control k8s]#  egrep -v '^#' /etc/kubernetes/controller-manager |grep -v '^$'
KUBE_CONTROLLER_MANAGER_ARGS="--node-monitor-grace-period=10s --pod-eviction-timeout=10s"

[root@Control k8s]#      egrep -v '^#' /etc/kubernetes/config | egrep -v '^$'
KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://192.168.5.2:8080"


[root@Control k8s]# cat master_start.sh
 systemctl enable kube-apiserver kube-scheduler kube-controller-manager
 systemctl start kube-apiserver kube-scheduler kube-controller-manager

 ss -antl 检查8080是否成功

node服务配置启动

[root@Resources-s1 k8s]# egrep -v '^#' /etc/kubernetes/config | grep -v '^$'
KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://192.168.5.2:8080"

[root@Resources-s1 k8s]# egrep -v '^#' /etc/kubernetes/kubelet | grep -v '^$'
KUBELET_ADDRESS="--address=127.0.0.1"
KUBELET_HOSTNAME="--hostname-override=192.168.5.3"
KUBELET_API_SERVER="--api-servers=http://192.168.5.2:8080"
KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"
KUBELET_ARGS=""

[root@Resources-s1 k8s]# cat node_start.sh
systemctl enable kubelet kube-proxy
systemctl start kubelet kube-proxy

网络配置

etcd配置内网信息

etcdctl -C 192.168.5.2:2379 set /playcrab-inc.com/network/config '{ "Network": "10.1.0.0/16" }'

node配置flanneld

[root@Resources-s1 k8s]# egrep -v '^#' /etc/sysconfig/flanneld | grep -v '^$'
FLANNEL_ETCD="http://192.168.5.2:2379"
FLANNEL_ETCD_KEY="/playcrab-inc.com/network"

[root@Resources-s1 k8s]# cat flanneld_start.sh
#systemctl enable  flanenld
systemctl restart flanneld

[root@Resources-s1 k8s]# cat docker_start.sh
systemctl enable docker
systemctl restart docker

检查集群启动情况

[root@Control k8s]#  kubectl get nodes
NAME          STATUS    AGE
192.168.5.3   Ready     28m
192.168.5.4   Ready     25m

======================================================

docker私有仓库建立

环境说明

我们选取192.168.5.2做私有仓库地址
yum install docker -y

1.启动docker仓库端口服务

docker run -d -p 5000:5000 --privileged=true -v /data/history:/data/registry registry  

[root@Control docker_dw_images]# docker images
REPOSITORY           TAG                 IMAGE ID            CREATED             SIZE
docker.io/registry   latest              c9bd19d022f6        6 weeks ago         33.27 MB

2.查看docker仓库端口服务

# curl -XGET http://192.168.5.2:5000/v2/_catalog
# curl -XGET http://192.168.5.2:5000/v2/image_name/tags/list

3.将自己的镜像加到docker仓库

1.1自己做基础镜像并加载到docker中
    cd centos6-image && tar -c .|docker import - centos6-base
1.2 创建一个带ssh的基础镜像
    mkdir centos6-ssh
    cd centos6-ssh
    vim  Dockerfile
    输入
    FROM centos6-base
    MAINTAINER wuqichao <wuqichao@playcrab.com>
    RUN ssh-keygen -q -N "" -t dsa -f /etc/ssh/ssh_host_dsa_key
    RUN ssh-keygen -q -N "" -t rsa -f /etc/ssh/ssh_host_rsa_key
    RUN sed -ri 's/session    required     pam_loginuid.so/#session    required     pam_loginuid.so/g' /etc/pam.d/sshd
    RUN mkdir -p /root/.ssh && chown root.root /root && chmod 700 /root/.ssh
    EXPOSE 22
    RUN echo 'root:xxx.com.cn' | chpasswd
    ENV LANG en_US.UTF-8
    ENV LC_ALL en_US.UTF-8
    CMD /usr/sbin/sshd -D
    保存退出
    运行如下指令
    docker build -t centos6-ssh .
    不报错的话，就完成本地镜像
1.3 测试启动ssh的基础镜像
    docker run -d -p 127.0.0.1:33333:22 centos6-ssh
1.4 登录ssh的基础镜像实例
    ssh root@127.0.0.1 -p 33333



2.加载到自己的私有仓库
    ###docker pull docker.io/nginx
    如果是本地建立docker不用执行上面的
    docker tag centos6-ssh 192.168.5.2:5000/centos6-ssh
    docker push 192.168.5.2:5000/centos6-ssh

3.检查是否成功    
 [root@Control k8s]# curl -XGET http://192.168.5.2:5000/v2/_catalog
{"repositories":["centos6-ssh"]}

k8s中使用docker私有仓库

环境设置

1.1.设置服务端

[root@Control k8s_yaml]# cat /etc/sysconfig/docker|grep 192.168.5.2
OPTIONS='--insecure-registry 192.168.5.2:5000 --log-driver=journald'
ADD_REGISTRY='--add-registry 192.168.5.2:5000'

1.2.设置客户端

[root@Control k8s]# cat /etc/default/docker
DOCKER_OPTS="--insecure-registry 192.168.5.2:5000"

1.3.去掉权限验证

在/etc/kubernetes/apiserver中
去除 KUBE_ADMISSION_CONTROL中的 SecurityContextDeny,ServiceAccount，
并重启kube-apiserver.service服务
#systemctl restart kube-apiserver.service

1.4.加上DNS服务不然后报错

KUBELET_ARGS="--cluster-dns=192.168.5.2 --cluster-domain=playcrab-inc.com"

配置YAML

2.0 常用指令

启动指令    
 kubectl create -f centos6-ssh/centos6-ssh.yaml

删除指令    
kubectl delete -f centos6-ssh/centos6-ssh.yaml

查看指令    
kubectl get pods

查看细节指令 
kubectl describe pod centos6-ssh

2.1启动最简单的pod

2.1.1 yaml配置

[root@Control k8s_yaml]# cat centos6-ssh/centos6-ssh.yaml
apiVersion: v1
kind: Pod
metadata:
  name: centos6-ssh
spec:
  containers:
  - name: centos6-ssh
    image: centos6-ssh

2.1.2 查看指令

[root@Control k8s_yaml]# kubectl get pods
NAME                READY     STATUS    RESTARTS   AGE
centos6-ssh-mucsv   1/1       Running   0          10m

2.1.3 查看细节指令

kubectl describe pod centos6-ssh  

[root@Control k8s_yaml]# kubectl describe pod centos6-ssh
Name:       centos6-ssh
Namespace:  default
Node:       192.168.5.3/192.168.5.3
Start Time: Wed, 30 Nov 2016 13:44:51 -0500
Labels:     <none>
Status:     Running
IP:     10.1.75.2
Controllers:    <none>
Containers:
  centos6-ssh:
    Container ID:   docker://7046491f05e3d549c198009f056b4e3e0508ad179712772bb296d0d08cc6ae29
    Image:      centos6-ssh
    Image ID:       docker://sha256:6525d364d418ae8dc854e6839dfaa653f2b6cd39c696a2f146bb918e69c20060
    Port:
    QoS Tier:
      cpu:      BestEffort
      memory:       BestEffort
    State:      Running
      Started:      Wed, 30 Nov 2016 13:44:52 -0500
    Ready:      True
    Restart Count:  0
    Environment Variables:
Conditions:
  Type      Status
  Ready     True
No volumes.
No events.

可以确认docker的实例跑在192.168.5.3这个NODE节点，分配到的集群内网IP为10.1.75.2
我们现在如果需要登录10.1.75.2要到192.168.5.3这个服务，ssh root@10.1.75.2,才可以登录

2.2启动多份的pod

2.2.1 yaml配置

我们定义了一个centos6-ssh pod复制器，复制份数为2，使用centos6-ssh镜像。

[root@Control k8s_yaml]# cat test/centos6-ssh-rc.yaml
apiVersion: v1
kind: ReplicationController
metadata:
  name: centos6-ssh
spec:
  replicas: 2
  selector:
    name: centos6-ssh
  template:
    metadata:
      labels:
        name: centos6-ssh
    spec:
      containers:
        - name: centos6-ssh
          image: centos6-ssh
          ports:
            - containerPort: 22

2.2.2 查看指令

[root@Control k8s_yaml]# kubectl get pods
NAME                READY     STATUS    RESTARTS   AGE
centos6-ssh-mucsv   1/1       Running   0          10m
centos6-ssh-yoghv   1/1       Running   0          10m

2.2.3 查看细节指令

[root@Control k8s_yaml]# kubectl describe pod centos6-ssh
Name:       centos6-ssh-mucsv
Namespace:  default
Node:       192.168.5.3/192.168.5.3
Start Time: Thu, 01 Dec 2016 11:04:24 -0500
Labels:     name=centos6-ssh
Status:     Running
IP:     10.1.75.2
Controllers:    ReplicationController/centos6-ssh
Containers:
  centos6-ssh:
    Container ID:   docker://ba9327de6f067b46ce348f409e9efa2b44a9064c4f1ea508cf7d92ff9c450541
    Image:      centos6-ssh
    Image ID:       docker://sha256:6525d364d418ae8dc854e6839dfaa653f2b6cd39c696a2f146bb918e69c20060
    Port:       22/TCP
    QoS Tier:
      memory:       BestEffort
      cpu:      BestEffort
    State:      Running
      Started:      Thu, 01 Dec 2016 11:04:25 -0500
    Ready:      True
    Restart Count:  0
    Environment Variables:
Conditions:
  Type      Status
  Ready     True
No volumes.
Events:
  FirstSeen LastSeen    Count   From            SubobjectPath           Type        Reason          Message
  --------- --------    -----   ----            -------------           --------    ------          -------
  5h        5h      2   {kubelet 192.168.5.3}                   Warning     MissingClusterDNS   kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to DNSDefault policy.
  5h        5h      1   {kubelet 192.168.5.3}   spec.containers{centos6-ssh}    Normal      Pulling         pulling image "centos6-ssh"
  5h        5h      1   {kubelet 192.168.5.3}   spec.containers{centos6-ssh}    Normal      Pulled          Successfully pulled image "centos6-ssh"
  5h        5h      1   {kubelet 192.168.5.3}   spec.containers{centos6-ssh}    Normal      Created         Created container with docker id ba9327de6f06
  5h        5h      1   {kubelet 192.168.5.3}   spec.containers{centos6-ssh}    Normal      Started         Started container with docker id ba9327de6f06
  3m        3m      1   {default-scheduler }                    Normal      Scheduled       Successfully assigned centos6-ssh-mucsv to 192.168.5.3

Name:       centos6-ssh-yoghv
Namespace:  default
Node:       192.168.5.4/192.168.5.4
Start Time: Thu, 01 Dec 2016 11:04:37 -0500
Labels:     name=centos6-ssh
Status:     Running
IP:     10.1.68.2
Controllers:    ReplicationController/centos6-ssh
Containers:
  centos6-ssh:
    Container ID:   docker://221e4335774a8347a74fa7341f947954e3fb0eccff5fce7be427b532a4f5d31f
    Image:      centos6-ssh
    Image ID:       docker://sha256:6525d364d418ae8dc854e6839dfaa653f2b6cd39c696a2f146bb918e69c20060
    Port:       22/TCP
    QoS Tier:
      cpu:      BestEffort
      memory:       BestEffort
    State:      Running
      Started:      Thu, 01 Dec 2016 11:04:38 -0500
    Ready:      True
    Restart Count:  0
    Environment Variables:
Conditions:
  Type      Status
  Ready     False
No volumes.
Events:
  FirstSeen LastSeen    Count   From            SubobjectPath           Type        Reason          Message
  --------- --------    -----   ----            -------------           --------    ------          -------
  5h        5h      2   {kubelet 192.168.5.4}                   Warning     MissingClusterDNS   kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to DNSDefault policy.
  5h        5h      1   {kubelet 192.168.5.4}   spec.containers{centos6-ssh}    Normal      Pulling         pulling image "centos6-ssh"
  5h        5h      1   {kubelet 192.168.5.4}   spec.containers{centos6-ssh}    Normal      Pulled          Successfully pulled image "centos6-ssh"
  5h        5h      1   {kubelet 192.168.5.4}   spec.containers{centos6-ssh}    Normal      Created         Created container with docker id 221e4335774a
  5h        5h      1   {kubelet 192.168.5.4}   spec.containers{centos6-ssh}    Normal      Started         Started container with docker id 221e4335774a
  3m        3m      1   {default-scheduler }                    Normal      Scheduled       Successfully assigned centos6-ssh-yoghv to 192.168.5.4

可以确认启动了两个实例 
10.1.75.2实例在192.168.5.3上
10.1.68.2实例在192.168.5.4上
如果需要SSH连接上去操作还是需要登到各自的物理机上去才可操作

2.3启动内网可访问的services

2.3.1 yaml配置

[root@Control k8s_yaml]# cat test/centos6-ssh-clusterip.yaml
apiVersion: v1
kind: Service
metadata:
  name: centos6-ssh-clusterip
spec:
  ports:
    - port: 2222
      targetPort: 22
      protocol: TCP
  selector:
    name: centos6-ssh

selector中的name必须和rc或者pod保持一致

2.3.2 查看

[root@Control k8s_yaml]# kubectl get service
NAME                    CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
centos6-ssh-clusterip   10.254.155.14   <none>        2222/TCP   3s
kubernetes              10.254.0.1      <none>        443/TCP    1d
[root@Control k8s_yaml]# kubectl describe service centos6-ssh-clusterip
Name:           centos6-ssh-clusterip
Namespace:      default
Labels:         <none>
Selector:       name=centos6-ssh
Type:           ClusterIP
IP:         10.254.155.14
Port:           <unset> 2222/TCP
Endpoints:      10.1.68.2:22,10.1.75.2:22
Session Affinity:   None
No events.

上面可以确认centos6-ssh-clusterip已经启动，分配到的IP为10.254.155.14，开启2222端口
代理Endpoints:        10.1.68.2:22,10.1.75.2:22

2.3.3 登录测试

[root@Resources-s1 ~]# telnet 10.254.155.14 2222
Trying 10.254.155.14...
Connected to 10.254.155.14.
Escape character is '^]'.
SSH-2.0-OpenSSH_5.3
^Cxx
Connection closed by foreign host.

QA:

1.解决https问题

[root@Control k8s]# docker push 192.168.5.2:5000/centos6-ssh
The push refers to a repository [192.168.5.2:5000/centos6-ssh]
unable to ping registry endpoint https://192.168.5.2:5000/v0/
v2 ping attempt failed with error: Get https://192.168.5.2:5000/v2/: http: server gave HTTP response to HTTPS client
 v1 ping attempt failed with error: Get https://192.168.5.2:5000/v1/_ping: http: server gave HTTP response to HTTPS client

要解决这个问题要在服务端和客户端改配置

服务端：
 [root@Control k8s]# cat /etc/sysconfig/docker|grep 192.168.5.2
 OPTIONS='--insecure-registry 192.168.5.2:5000 --log-driver=journald'
 ADD_REGISTRY='--add-registry 192.168.5.2:5000'

客户端：
[root@Control k8s]# cat /etc/default/docker
DOCKER_OPTS="--insecure-registry 192.168.5.2:5000"

2.解决创建成功但是kubectl get pods 没有的问题

Error from server: error when creating "nginx.yaml": Pod "nginx" is forbidden: no API token found for service account default/default, retry after the token is automatically created and added to the service account

要解决这个问题如下：

创建pod:
# kubectl create -f nginx.yaml
此时有如下报错：

Error from server: error when creating "nginx.yaml": Pod "nginx" is forbidden: no API token found for service account default/default, retry after the token is automatically created and added to the service account
解决办法是编辑/etc/kubernetes/apiserver 去除 KUBE_ADMISSION_CONTROL中的SecurityContextDeny,ServiceAccount，并重启kube-apiserver.service服务：

#vim /etc/kubernetes/apiserver
KUBE_ADMISSION_CONTROL="--admission_control=NamespaceLifecycle,NamespaceExists,LimitRanger,ResourceQuota"

#systemctl restart kube-apiserver.service
之后重新创建pod:

# kubectl create -f nginx.yaml
pods/nginx

playcrab.com.cn

3. ClusterDNS 出问题，pod不成功

kubelet does not have ClusterDNS IP configured and cannot create Pod using "ClusterFirst" policy. Falling back to DNSDefault policy.

这样解决
KUBELET_ARGS="--cluster-dns=192.168.5.2 --cluster-domain=playcrab-inc.com"