Docker鏡像制作（以Nginx+Keepalived為例）（beta）

 簡述

本文主要介紹如何制作鏡像。以制作nginx-keepalived為例並提交到私服；

 

鏡像制作思路

基於Nginx官方鏡像安裝Keepalived等軟件；

第一步，編寫制作Dockerfile文件（也可通過其他方式：例如通過docker commit來制作新的鏡像）

FROM nginx

ARG TZ="Asia/Shanghai"

ENV TZ ${TZ}

COPY keepalived/  /etc/keepalived
COPY docker-entrypoint-n.sh /

RUN apt-get update  \
    && apt-get install -y keepalived \
    && apt install -y procps \
    && apt install -y vim \
    && chmod +x /etc/keepalived/chk_nginx.sh \
    && chmod +x /docker-entrypoint-n.sh

ENTRYPOINT ["/docker-entrypoint-n.sh"]

CMD ["nginx", "-g",  "daemon off;" ]

 

第二步，編譯dockerfile文件

在終端cd進入Dockerfile所在文件夾目錄，執行編譯命令

#最后點號是表示編譯的目錄，具體命令解釋見參考鏈接
docker build -t nginx-keepalived:0.0.1 .

執行過程如下

whroiddeMacBook-Pro:keepalived-nginx whroid$ docker build -t nginx-keepalived:0.0.1 .
Sending build context to Docker daemon  16.38kB
Step 1/8 : FROM nginx
 ---> 4bb46517cac3
Step 2/8 : ARG TZ="Asia/Shanghai"
 ---> Using cache
 ---> 01e995bfa2bb
Step 3/8 : ENV TZ ${TZ}
 ---> Using cache
 ---> 25e3fadc1f14
Step 4/8 : COPY keepalived/  /etc/keepalived
 ---> Using cache
 ---> 3ba0f80fcae8
Step 5/8 : COPY docker-entrypoint-n.sh /
 ---> Using cache
 ---> a6d47fcd5a3a
Step 6/8 : RUN apt-get update      && apt-get install -y keepalived     && apt install -y procps     && apt install -y vim     && chmod +x /etc/keepalived/chk_nginx.sh     && chmod +x /docker-entrypoint-n.sh
 ---> Using cache
 ---> b6a28651011b
Step 7/8 : ENTRYPOINT ["/docker-entrypoint-n.sh"]
 ---> Using cache
 ---> 3270b0c5f3f8
Step 8/8 : CMD ["nginx", "-g",  "daemon off;" ]
 ---> Using cache
 ---> 0599e6de7c88
Successfully built 0599e6de7c88
Successfully tagged nginx-keepalived:0.0.1

 

編譯成功后使用”docker images“查看編譯的鏡像信息

REPOSITORY                                                     TAG                 IMAGE ID            CREATED             SIZE

nginx-keepalived                                               0.0.1               0599e6de7c88        41 hours ago        249MB

 

第三步，運行鏡像容器，並驗證是否符合要求

進入容器：docker run -d --privileged --name nginx-keepalived001 nginx-keepalived:0.0.1

以下相關運行情況

 

 

第四步，上傳鏡像文件到私服

這里的私服是直接上傳到阿里雲，如果自己搭建私服也是一樣的操作

推送鏡像到阿里雲私服Registry，具體的倉庫名稱以及私服地址根據實際情況調整
$ sudo docker login --username=用戶名 registry.cn-zhangjiakou.aliyuncs.com
$ sudo docker tag [ImageId] registry.cn-zhangjiakou.aliyuncs.com/whroid/nginx-keepalived:[鏡像版本號]
$ sudo docker push registry.cn-zhangjiakou.aliyuncs.com/whroid/nginx-keepalived:[鏡像版本號]

注：需要先登錄到具體私服，然后給鏡像建立tag，之后將tag推送到遠端私服上；

經過上面一步操作之后，在本地通過docker images命令可以查看

查看到鏡像已經上傳到阿里雲私服

 

第五步，從私服下載鏡像

$ sudo docker pull registry.cn-zhangjiakou.aliyuncs.com/whroid/nginx-keepalived:[鏡像版本號]

 

 

 注：

1，鏡像不帶倉庫地址的默認使用的都是官方公開倉庫。https://hub.docker.com/

 

附錄

鏡像文件其他文件

1，鏡像目錄結構

 

2，chk_nginx.sh文件

#!/bin/bash
run=`ps -C nginx --no-header | wc -l`
if [ $run -eq 0 ]; then
    service nginx start
    sleep 3
    if [ `ps -C nginx --no-header | wc -l` -eq 0 ]; then
        service keepalived stop
    fi
fi

3，keepalived.conf文件

global_defs {
   router_id NKEEP_MASTER       #唯一標識，不能重復
   vrrp_skip_check_adv_addr
   #vrrp_strict
   vrrp_garp_interval 1
   vrrp_gna_interval 1
}

vrrp_script chk_nginx {         
    script "/etc/keepalived/chk_nginx.sh"   
    interval 2             
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0  #所屬網絡
    virtual_router_id 51
    priority 100  #權重
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.17.0.100 #vip虛擬地址
    }
    track_script {
       chk_nginx #調用執行腳本的函數，上面已經定義該函數
    }
}

4，docker-entrypoint-h.sh

#!/bin/sh
# vim:sw=4:ts=4:et

set -e

if [ -z "${NGINX_ENTRYPOINT_QUIET_LOGS:-}" ]; then
    exec 3>&1
else
    exec 3>/dev/null
fi

if [ "$1" = "nginx" -o "$1" = "nginx-debug" ]; then
    if /usr/bin/find "/docker-entrypoint.d/" -mindepth 1 -maxdepth 1 -type f -print -quit 2>/dev/null | read v; then
        echo >&3 "$0: /docker-entrypoint.d/ is not empty, will attempt to perform configuration"

        echo >&3 "$0: Looking for shell scripts in /docker-entrypoint.d/"
        find "/docker-entrypoint.d/" -follow -type f -print | sort -n | while read -r f; do
            case "$f" in
                *.sh)
                    if [ -x "$f" ]; then
                        echo >&3 "$0: Launching $f";
                        "$f"
                    else
                        # warn on shell scripts without exec bit
                        echo >&3 "$0: Ignoring $f, not executable";
                    fi
                    ;;
                *) echo >&3 "$0: Ignoring $f";;
            esac
        done

        echo >&3 "$0: Configuration complete; ready for start up"
    else
        echo >&3 "$0: No files found in /docker-entrypoint.d/, skipping configuration"
    fi
fi

exec "$@"

exec "service keepalived start"

 

參考：

1，docker基礎教程：https://www.runoob.com/docker/docker-dockerfile.html

2，docker官方文檔：https://docs.docker.com/engine/reference/builder/ 

3，keepalived源碼編譯安裝：https://www.cnblogs.com/yuanpeng-java/p/10022061.html 

4，keepalived官方地址：https://www.keepalived.org/ 

5，nginx官方下載地址：http://nginx.org/en/download.html