docker文件存放路径, 获取容器启动命令
如何获取容器的启动命令
- 容器早已创建好，如何得知它的启动参数(数据挂载到哪)
#假设通过如下命令启动了一个容器
docker run -d --name mysql\
-p 3306:3306\
-e MYSQL_ROOT_PASSWORD=123456\
--restart=always\
mysql:5.5 --character-set-server=utf8
#如何通过容器名得知启动参数
[root@jenkins ~]# docker inspect mysql_cdh
[
{
"Id": "fbc3fba81b57bc5b5871746098b5f1f7ef0ed7716a786584a5effbb88ba156e6",
"Created": "2019-09-25T01:43:37.720505875Z",
"Path": "docker-entrypoint.sh",
"Args": [
"--character-set-server=utf8"
],
"HostConfig": {
"Binds": [
"mysql-data:/var/lib/mysql"
],
"ContainerIDFile": "",
"LogConfig": {
"Type": "json-file",
"Config": {}
},
"NetworkMode": "default",
"PortBindings": {
"3306/tcp": [{ "HostIp": "", "HostPort": "3306"}
]
},
"RestartPolicy": {
"Name": "always",
"MaximumRetryCount": 0
},
"Mounts": [
{
"Type": "volume",
"Name": "mysql-data",
"Source": "/var/lib/docker/volumes/mysql-data/_data",
"Destination": "/var/lib/mysql",
"Driver": "local",
"Mode": "z",
"RW": true,
"Propagation": ""
}
],
1, 镜像层：文件存放路径
[root@master ~]# docker image inspect nginx |tail -n 22
"GraphDriver": {
"Data": {
"LowerDir": "/var/lib/docker/overlay2/bf20cf788cc053f00ff1467525d50e19bd1cf07a2167f72511bdfcb28918a472/diff:/var/lib/docker/overlay2/317d80bb7ae58ed288be9ebd84aeb5b4b3a1c06f3211f5d1f32d89b629d1876e/diff",
"MergedDir": "/var/lib/docker/overlay2/7782d0eb292fdc8bbd73bf9bae2d65468e8aba0bcd6baed55ac348618b80ae16/merged",
"UpperDir": "/var/lib/docker/overlay2/7782d0eb292fdc8bbd73bf9bae2d65468e8aba0bcd6baed55ac348618b80ae16/diff",
"WorkDir": "/var/lib/docker/overlay2/7782d0eb292fdc8bbd73bf9bae2d65468e8aba0bcd6baed55ac348618b80ae16/work"
},
"Name": "overlay2"
},
2, 容器层：文件存放路径
#1, 启动容器
[root@master ~]# docker run -d --name nginx2 nginx
a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8
#2, 获取容器id
[root@master ~]# docker inspect nginx2 | grep -i id
[root@master ~]# docker inspect nginx2 | grep -i id
"Id": "a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8",
"Pid": 2069,
"ExecIDs": null,
"ContainerIDFile": "",
#查看容器临时文件--每次创建时随机生成的文件(容器层)
[root@master ~]# docker inspect nginx2 | grep -i path
"Path": "nginx",
"ResolvConfPath": "/var/lib/docker/containers/a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8/resolv.conf",
"HostnamePath": "/var/lib/docker/containers/a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8/hostname",
"HostsPath": "/var/lib/docker/containers/a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8/hosts",
"LogPath": "/var/lib/docker/containers/a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8/a9c9f31cdccf13c3385f3de33443325d2e14d69458e6d679e54c8cf9e5ff24c8-json.log",
#通过容器id, 查找容器数据存放目录： /var/lib/docker/overlay2/容器id
######
#对比上面的“镜像层：文件存放路径”，可以看到 :容器通过LowerDir 挂载的方式，映射了镜像层的文件
######
[root@master ~]# docker inspect nginx2 | grep -i dir
"LowerDir": "/var/lib/docker/overlay2/d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b-init/diff:/var/lib/docker/overlay2/7782d0eb292fdc8bbd73bf9bae2d65468e8aba0bcd6baed55ac348618b80ae16/diff:/var/lib/docker/overlay2/bf20cf788cc053f00ff1467525d50e19bd1cf07a2167f72511bdfcb28918a472/diff:/var/lib/docker/overlay2/317d80bb7ae58ed288be9ebd84aeb5b4b3a1c06f3211f5d1f32d89b629d1876e/diff",
"MergedDir": "/var/lib/docker/overlay2/d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b/merged",
"UpperDir": "/var/lib/docker/overlay2/d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b/diff",
"WorkDir": "/var/lib/docker/overlay2/d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b/work"
后天修改容器端口
通过容器层文件，找到配置文件hostconfig.json，修改容器映射的端口
[root@docker d93185e3a0....2e544ccfa]# pwd
/var/lib/docker/containers/d93185e3a0....2e544ccfa
[root@docker d93185e3a0....2e544ccfa]# cat hostconfig.json
{"Binds":["/dockersuperset:/home/superset"],"ContainerIDFile":"",
"LogConfig":{"Type":"json-file","Config":{}},"NetworkMode":"default",
"PortBindings":{"8088/tcp":[{"HostIp":"","HostPort":"8099"}]}......
3, 进入镜容器文件存储目录， 修改配置文件
# 进入镜容器文件存储目录， 修改配置文件
[root@master ~]# cd /var/lib/docker/overlay2/d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# ls
diff link lower merged work
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# ls diff/run/
nginx.pid
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# ls diff/var/cache/nginx/
client_temp fastcgi_temp proxy_temp scgi_temp uwsgi_temp
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# ls merged/
bin/ dev/ etc/ lib/ media/ opt/ root/ sbin/ sys/ usr/
boot/ .dockerenv home/ lib64/ mnt/ proc/ run/ srv/ tmp/ var/
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# ls merged/etc/nginx/
conf.d fastcgi_params koi-utf koi-win mime.types modules nginx.conf scgi_params uwsgi_params win-utf
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# head merged/etc/nginx/nginx.conf
user nginx;
worker_processes 1;
#在此处修改配置文件，把user nginx; worker_process 1; 这两行的分号去掉，看容器里面的配置是否更改
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# head merged/etc/nginx/nginx.conf -n 3
user nginx
worker_processes 1
#登陆容器，查看修改的配置： 验证是否生效
[root@master d37ff828e63081be6fcfefc73891e7b455596cb921c8021fbf9571f330c0599b]# docker exec -it nginx2 bash
root@a9c9f31cdccf:/# head /etc/nginx/nginx.conf -n 3
user nginx
worker_processes 1
4, 修改默认存储路径
a, 重建/var/lib/docker目录
#备份数据到新的存放路径
service docker stop
mkdir /docker.bak
mv /var/lib/docker/* /docker.bak
#创建软连接
mkdir /home/docker-data
mv /docker.bak/* /home/docker-data/ && rmdir /docker.bak
ln -s /home/docker-data /var/lib/docker
b, 修改配置
vi /usr/lib/systemd/system/docker.service
ExecStart=/usr/bin/dockerd --graph /new-path/docker
#reload配置文件
systemctl daemon-reload
#重启docker
systemctl restart docker.service
