1.打包应用 到容器中 2.隔离 3.启动快
Docker 镜像(Image)就是一个只读的模板。例如:一个镜像可以包含一个完整的操作系统环境,里面仅安装了 Apache 或用户需要的其它应用程序。镜像可以用来创建 Docker 容器,一个镜像可以创建很多容器。
仓库(Repository)是集中存放镜像文件的场所,docker hub。
Docker 利用容器(Container)来运行应用。容器是从镜像创建的运行实例。它可以被启动、开始、停止、删除。每个容器都是相互隔离的、保证安全的平台。可以把容器看做是一个简易版的 Linux 环境(包括root用户权限、进程空间、用户空间和网络空间等)和运行在其中的应用程序。
https://docs.docker.com/install/linux/docker-ce/centos/
//查看镜像
docker images
//查询centos镜像
docker search centos
//拉取tag为6.8的centos
docker pull centos:6.8
//运行容器,并登录终端
docker run -it centos:6.8 /bin/bash
docker run -d xujd_v2/blog_image /bin/bash -c "while true; do echo hello world; sleep 1; done"
//停止一个正在运行的容器
docker stop c1e43f1b4c40
//启动一个容器,之前使用过docker run运行过的
docker start
//docker run 和 docker start区别
docker run只在第一次运行时使用,将镜像放到容器中,以后再次启动这个容器时,只需要使用命令docker start 即可
// 进入一个已经在运行的容器
sudo docker exec -it c1e43f1b4c40 /bin/bash
//查看正在运行的容器
docker ps
//查看所有的容器
docker ps -a
//删除容器,必须要先stop
docker rm
//删除镜像,必须先删除容器,
docker rmi xxxx
//提供用户交互的输入
-i
//进入镜像终端
-t
//后台运行
-d
//映射端口
-p
//查看docker容器详情
docker inspect c13c4f513eab
[
{
"Id": "c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e",
"Created": "2019-04-23T02:34:15.419464005Z",
"Path": "/bin/bash",
"Args": [],
"State": {
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 28969,
"ExitCode": 0,
"Error": "",
"StartedAt": "2019-04-23T03:13:29.799806806Z",
"FinishedAt": "2019-04-23T02:36:17.837234697Z"
},
"Image": "efa3cf7ee1f93d75578007edf881ddc2cc048e9da03503f103c819b157f94b75",
"NetworkSettings": {
"Bridge": "",
"EndpointID": "49c648da46dcc4e2f794fc146cfb969fa4cdf89c1d159534cd8a701cf9f9a811",
"Gateway": "172.17.42.1",
"GlobalIPv6Address": "",
"GlobalIPv6PrefixLen": 0,
"HairpinMode": false,
"IPAddress": "172.17.0.19",
"IPPrefixLen": 16,
"IPv6Gateway": "",
"LinkLocalIPv6Address": "",
"LinkLocalIPv6PrefixLen": 0,
"MacAddress": "02:42:ac:11:00:13",
"NetworkID": "1d5d60cb383beaed8c57ba5edc08129e82b78cf2cdb95e9b8bdfe49c4f923d0e",
"PortMapping": null,
"Ports": {},
"SandboxKey": "/var/run/docker/netns/c13c4f513eab",
"SecondaryIPAddresses": null,
"SecondaryIPv6Addresses": null
},
"ResolvConfPath": "/var/lib/docker/containers/c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e/hostname",
"HostsPath": "/var/lib/docker/containers/c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e/hosts",
"LogPath": "/var/lib/docker/containers/c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e/c13c4f513eab415ad355ba7607392a84d69cb0ba0018739cf3e040780a148d4e-json.log",
"Name": "/naughty_lalande",
"RestartCount": 0,
"Driver": "devicemapper",
"ExecDriver": "native-0.2",
"MountLabel": "",
"ProcessLabel": "",
"Volumes": {},
"VolumesRW": {},
"AppArmorProfile": "",
"ExecIDs": null,
"HostConfig": {
"Binds": null,
"ContainerIDFile": "",
"LxcConf": [],
"Memory": 0,
"MemorySwap": 0,
"CpuShares": 0,
"CpuPeriod": 0,
"CpusetCpus": "",
"CpusetMems": "",
"CpuQuota": 0,
"BlkioWeight": 0,
"OomKillDisable": false,
"Privileged": false,
"PortBindings": {},
"Links": null,
"PublishAllPorts": false,
"Dns": null,
"DnsSearch": null,
"ExtraHosts": null,
"VolumesFrom": null,
"Devices": [],
"NetworkMode": "bridge",
"IpcMode": "",
"PidMode": "",
"UTSMode": "",
"CapAdd": null,
"CapDrop": null,
"RestartPolicy": {
"Name": "no",
"MaximumRetryCount": 0
},
"SecurityOpt": null,
"ReadonlyRootfs": false,
"Ulimits": null,
"LogConfig": {
"Type": "json-file",
"Config": {}
},
"CgroupParent": ""
},
"Config": {
"Hostname": "c13c4f513eab",
"Domainname": "",
"User": "",
"AttachStdin": true,
"AttachStdout": true,
"AttachStderr": true,
"PortSpecs": null,
"ExposedPorts": null,
"Tty": true,
"OpenStdin": true,
"StdinOnce": true,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
],
"Cmd": [
"/bin/bash"
],
"Image": "centos:6.8",
"Volumes": null,
"VolumeDriver": "",
"WorkingDir": "",
"Entrypoint": null,
"NetworkDisabled": false,
"MacAddress": "",
"OnBuild": null,
"Labels": {
"build-date": "2016-06-02",
"license": "GPLv2",
"name": "CentOS Base Image",
"vendor": "CentOS"
}
}
}
]
1.使用已经存在的镜像,并更新提交形成新的镜像 2.使用 Dockerfile来指定创建新的镜像
//方式1
//更新镜像并提交成新的镜像
//-m:提交的描述信息 -a:指定镜像作者
//e218edb10161 镜像id
docker commit -m="has update" -a="runoob"
//方式2
//创建镜像 -t :指定要创建的目标镜像名
docker build -t runoob/centos:6.7 .
//设置镜像tag
docker tag 860c279d2fec runoob/centos:dev
创建java环境镜像 1.使用centos6.8做基础镜像 2.安装jdk 3.安装tomcat 4.配置环境变量并暴露端口
步骤 1.创建一个文件夹。
mkdir docker
2.将apache-tomcat-8.5.40.tar.gz jdk-8u144-linux-x64.tar.gz 复制到docker文件夹中 Dockerfile的文件中的相对路径是Dockerfile所在的目录
cp /usr/local/apache-tomcat-8.5.40.tar.gz ~/docker
cp /usr/local/jdk-8u144-linux-x64.tar.gz ~/docker
3.创建并编写Dockerfile文件
FROM centos:6.8
MAINTAINER xujd
ADD jdk-8u144-linux-x64.tar.gz /usr/local
ADD apache-tomcat-8.5.40.tar.gz /usr/local
ENV JAVA_HOME=/usr/local/jdk1.8.0_144
ENV PATH=$JAVA_HOME/bin:$PATH
ENV CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
EXPOSE 8080
FROM centos:6.8
MAINTAINER xujd
ADD jdk-8u144-linux-x64.tar.gz /usr/local
ADD apache-tomcat-8.5.40 /usr/local/apache-tomcat-8.5.40
ENV JAVA_HOME=/usr/local/jdk1.8.0_144
ENV PATH=$JAVA_HOME/bin:$PATH
ENV CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
ENV APP_ENCRYPTION_PASSWORD=123456
EXPOSE 8080
CMD ["/usr/local/apache-tomcat-8.5.40/bin/catalina.sh", "run"]
这个跟上面那个的区别是
上面的tomcat是tar ADD命令会自动解压,,没有war 到时候在使用挂载方式
下面 ADD apache-tomcat-8.5.40 /usr/local/apache-tomcat-8.5.40 apache-tomcat-8.5.40是一个目录不是tar.. 已经将要部署的war解压(jar xvf blog.war)放入tomcat的webapp目录中了
下面是自己手动解压(jar xvf blog.war)后的。。目标目录要自己创建(/usr/local/apache-tomcat-8.5.40)
不然会将源目录下面的文件 复制到/usr/local/下面而不是
/usr/local/apache-tomcat-8.5.40
4.构建 使用-t指定镜像名 .当前目录是docker目录
docker build -t xujd/blog_image .
//查看镜像 docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
xujd/blog_image latest 62ff846ee49c 2 hours ago 584.6 MB
5.运行容器
//第一个8080是本地的 第二个8080是docker -d后台运行
//catalina.sh run 启动容器的时候也启动tomcat
//可以在Dockerfile使用**CMD**命令来控制运行容器就启动tomcat就不要catalina.sh run
docker run -d -p 8081:8080 xujd/blog_image /usr/local/apache-tomcat-8.5.40/bin/catalina.sh run
//war是本博客的
//--env配置环境变量,因为配置文件密码加密
//-v将宿主机~/webapps/挂载docker中tomcat的webapps
docker run --env APP_ENCRYPTION_PASSWORD=123456 -d -p 8080:8080 -v ~/webapps/:/usr/local/apache-tomcat-8.5.40/webapps/ xujd/blog_image /usr/local/apache-tomcat-8.5.40/bin/catalina.sh run
注意1: 博客要连接数据库,数据库在宿主机上,所以docker需要连接外部数据库 docker数据库连接不能用127.0.0.1了要换成宿主机的ip(docker虚拟出来的网卡) 查看宿主机的ip docker0
//ifconfig
docker0 Link encap:Ethernet HWaddr 3E:AF:01:F7:09:61
inet addr:172.17.42.1 Bcast:0.0.0.0 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:8749 errors:0 dropped:0 overruns:0 frame:0
TX packets:22844 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1820508 (1.7 MiB) TX bytes:32405691 (30.9 MiB)
注意2:
数据库默认只能127.0.0.1才能访问所以要设置能其他ip访问
GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '123456' WITH GRANT OPTION;
flush privileges;
问题:
由于我重启了防火墙,但是没有重启docker,启动容器报错!!
docker0: iptables: No chain/target/match by that name
解决方案:重启docker: service restart docker
登录docker容器内部在/etc/profile,source /etc/profile配置环境变量不生效
解决方案:
1.Dockerfile配置文件使用env来配置 推荐
2.运行容器的时候使用--env来指定。上面就是这个做的/root/.bashrc
3.登录容器中配置在/root/.bashrc文件中(没试过)
docker pull 54288.top:/registry:2.1.
报错 http: server gave HTTP response to HTTPS client
在/etc/docker目录下新建daemon.json文件
[root@k8s-master1 kubernetes]# cat /etc/docker/daemon.json
{ "insecure-registries":["54288.top:5000"] }
参考https://www.cnblogs.com/hobinly/p/6110624.html