kubernetes（五）二进制安装-安装docker服务

部署docker服务（在master节点上执行）

1. 下载和分发 docker 二进制文件

   cd /opt/k8s/work
   wget https://download.docker.com/linux/static/stable/x86_64/docker-18.09.6.tgz
   tar -xvf docker-18.09.6.tgz
   

2. 分发二进制文件到所有 worker 节点

   cd /opt/k8s/work
   export node_ip=192.168.0.114
   scp docker/*  [email protected]${node_ip}:/opt/k8s/bin/
   ssh [email protected]${node_ip} "chmod +x /opt/k8s/bin/*"
   

3. 创建docker服务启动文件

   cd /opt/k8s/work
   cat > docker.service <<"EOF"
   [Unit]
   Description=Docker Application Container Engine
   Documentation=http://docs.docker.io
   
   [Service]
   WorkingDirectory=/data/k8s/docker
   Environment="PATH=/opt/k8s/bin:/bin:/sbin:/usr/bin:/usr/sbin"
   EnvironmentFile=-/run/flannel/docker
   ExecStart=/opt/k8s/bin/dockerd $DOCKER_NETWORK_OPTIONS
   ExecReload=/bin/kill -s HUP $MAINPID
   Restart=on-failure
   RestartSec=5
   LimitNOFILE=infinity
   LimitNPROC=infinity
   LimitCORE=infinity
   Delegate=yes
   KillMode=process
   
   [Install]
   WantedBy=multi-user.target
   EOF
   

   • EOF 前后有双引号，这样 bash 不会替换文档中的变量，如 $DOCKER_NETWORK_OPTIONS (这些环境变量是 systemd 负责替换的。)；

   • dockerd 运行时会调用其它 docker 命令，如 docker-proxy，所以需要将 docker 命令所在的目录加到 PATH 环境变量中；

   • flanneld 启动时将网络配置写入 /run/flannel/docker 文件中，dockerd 启动前读取该文件中的环境变量 DOCKER_NETWORK_OPTIONS ，然后设置 docker0 网桥网段；

   • docker 从 1.13 版本开始，可能将 iptables FORWARD chain的默认策略设置为DROP，从而导致 ping 其它 Node 上的 Pod IP 失败，遇到这种情况时，需要手动设置策略为 ACCEPT：

     export node_ip=192.168.0.114
     ssh [email protected]${node_ip}  "/sbin/iptables -P FORWARD ACCEPT"
     

4. 分发 docker.service 文件到所有 worker 机器:

   cd /opt/k8s/work
   export node_ip=192.168.0.114
   scp docker.service [email protected]${node_ip}:/etc/systemd/system/
   

5. 配置和分发 docker 配置文件

   使用国内的仓库镜像服务器以加快 pull image 的速度，同时增加下载的并发数 (需要重启 dockerd 生效)：

   cd /opt/k8s/work
   cat > docker-daemon.json <<EOF
   {
       "registry-mirrors": ["https://docker.mirrors.ustc.edu.cn","https://hub-mirror.c.163.com"],
       "max-concurrent-downloads": 20,
       "live-restore": true,
       "max-concurrent-uploads": 10,
       "data-root": "/data/k8s/docker/data",
       "log-opts": {
         "max-size": "100m",
         "max-file": "5"
       }
   }
   EOF
   
   

6. 分发 docker 配置文件到所有 worker 节点：

   cd /opt/k8s/work
   
   export node_ip=192.168.0.114
   ssh [email protected]${node_ip} "mkdir -p  /etc/docker/ /data/k8s/docker/data"
   scp docker-daemon.json [email protected]${node_ip}:/etc/docker/daemon.json
   

7. 启动 docker 服务

   export node_ip=192.168.0.114
   ssh [email protected]${node_ip} "systemctl daemon-reload && systemctl enable docker && systemctl restart docker"
   

8. 检查服务运行状态

   export node_ip=192.168.0.114
   ssh [email protected]${node_ip} "systemctl status docker|grep Active"
   

   • 确保状态为 active (running)，否则查看日志，确认原因

   • 如果出现异常，通过如下命令查看

     journalctl -u docker
     

9. 检查 docker0 网桥

   export node_ip=192.168.0.114
   ssh [email protected]${node_ip} "/sbin/ip addr show flannel.1 && /sbin/ip addr show docker0"
   

   • 确认各 worker 节点的 docker0 网桥和 flannel.1 接口的 IP 处于同一个网段中

     输出内容

     export node_ip=192.168.0.114
     [email protected]:/opt/k8s/work# ssh [email protected]${node_ip} "/sbin/ip addr show flannel.1 && /sbin/ip addr show docker0"
     4: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN group default
         link/ether f2:fc:0f:7e:98:e4 brd ff:ff:ff:ff:ff:ff
         inet 172.30.78.0/32 scope global flannel.1
            valid_lft forever preferred_lft forever
         inet6 fe80::f0fc:fff:fe7e:98e4/64 scope link
            valid_lft forever preferred_lft forever
     5: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default
         link/ether 02:42:fd:1f:8f:d8 brd ff:ff:ff:ff:ff:ff
         inet 172.30.78.1/24 brd 172.30.78.255 scope global docker0
            valid_lft forever preferred_lft forever
     
     

   • 注意: 如果您的服务安装顺序不对或者机器环境比较复杂, docker服务早于flanneld服务安装，此时 worker 节点的 docker0 网桥和 flannel.1 接口的 IP可能不会同处同一个网段下，这个时候请先停止docker服务, 手工删除docker0网卡，重新启动docker服务后即可修复

     systemctl stop docker
     ip link delete docker0
     systemctl start docker
     

10. 查看 docker 的状态信息

    [email protected]:/opt/k8s/work# docker info
    Containers: 0
     Running: 0
     Paused: 0
     Stopped: 0
    Images: 0
    Server Version: 18.09.6
    Storage Driver: overlay2
     Backing Filesystem: extfs
     Supports d_type: true
     Native Overlay Diff: true
    Logging Driver: json-file
    Cgroup Driver: cgroupfs
    Plugins:
     Volume: local
     Network: bridge host macvlan null overlay
     Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
    Swarm: inactive
    Runtimes: runc
    Default Runtime: runc
    Init Binary: docker-init
    containerd version: bb71b10fd8f58240ca47fbb579b9d1028eea7c84
    runc version: 2b18fe1d885ee5083ef9f0838fee39b62d653e30
    init version: fec3683
    Security Options:
     apparmor
     seccomp
      Profile: default
    Kernel Version: 5.0.0-23-generic
    Operating System: Ubuntu 18.04.3 LTS
    OSType: linux
    Architecture: x86_64
    CPUs: 4
    Total Memory: 3.741GiB
    Name: slave
    ID: IDMG:7A6F:UNTP:IWVM:ZBK5:VHJ4:STC5:UXZX:HQT6:UUNE:YDOC:I27L
    Docker Root Dir: /data/k8s/docker/data
    Debug Mode (client): false
    Debug Mode (server): false
    Registry: https://index.docker.io/v1/
    Labels:
    Experimental: false
    Insecure Registries:
     127.0.0.0/8
    Registry Mirrors:
     https://docker.mirrors.ustc.edu.cn/
     https://hub-mirror.c.163.com/
    Live Restore Enabled: true
    Product License: Community Engine
    
    WARNING: No swap limit support