podman的使用
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podman的使用
设置别名
[root@hzy ~]# alias
alias cp='cp -i'
alias docker='podman'
拉取镜像
[root@hzy ~]# docker pull nginx
Resolving "nginx" using unqualified-search registries (/etc/containers/registries.conf)
Trying to pull docker.io/library/nginx:latest...
Getting image source signatures
Copying blob 33847f680f63 skipped: already exists
Copying blob c90b090c213b done
Copying blob 1f41b2f2bf94 done
Copying blob dbb907d5159d done
Copying blob b10cf527a02d done
Copying blob 8a268f30c42a done
Copying config 08b152afcf done
Writing manifest to image destination
Storing signatures
08b152afcfae220e9709f00767054b824361c742ea03a9fe936271ba520a0a4b
运行容器
[root@hzy ~]# docker run -d --name nginx -p 80:80 nginx
bcb891fcc9e7ab89413ca418fd0cace16ba5d858110577ac3ee4a802250df28c
[root@hzy ~]# docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
bcb891fcc9e7 docker.io/library/nginx:latest nginx -g daemon o... 16 seconds ago Up 16 seconds ago 0.0.0.0:80->80/tcp nginx
[root@hzy ~]# curl 192.168.207.137
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
查看容器的详细信息
[root@hzy ~]# docker inspect -l //-l表示最后创建的容器
[
{
"Id": "bcb891fcc9e7ab89413ca418fd0cace16ba5d858110577ac3ee4a802250df28c",
"Created": "2021-08-13T09:45:41.302784855+08:00",
"Path": "/docker-entrypoint.sh",
"Args": [
"nginx",
"-g",
"daemon off;"
],
"State": {
"OciVersion": "1.0.2-dev",
"Status": "running",
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 19936,
……
查看容器日志
[root@hzy ~]# docker logs -f -l
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up
2021/08/13 01:45:41 [notice] 1#1: using the "epoll" event method
2021/08/13 01:45:41 [notice] 1#1: nginx/1.21.1
2021/08/13 01:45:41 [notice] 1#1: built by gcc 8.3.0 (Debian 8.3.0-6)
2021/08/13 01:45:41 [notice] 1#1: OS: Linux 4.18.0-257.el8.x86_64
2021/08/13 01:45:41 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2021/08/13 01:45:41 [notice] 1#1: start worker processes
2021/08/13 01:45:41 [notice] 1#1: start worker process 31
2021/08/13 01:45:41 [notice] 1#1: start worker process 32
2021/08/13 01:45:41 [notice] 1#1: start worker process 33
2021/08/13 01:45:41 [notice] 1#1: start worker process 34
192.168.207.131 - - [13/Aug/2021:01:46:04 +0000] "GET / HTTP/1.1" 200 612 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36 Edg/92.0.902.67" "-"
2021/08/13 01:46:04 [error] 31#31: *1 open() "/usr/share/nginx/html/favicon.ico" failed (2: No such file or directory), client: 192.168.207.131, server: hzy, request: "GET /favicon.ico HTTP/1.1", host: "192.168.207.137", referrer: "http://192.168.207.137/"
192.168.207.131 - - [13/Aug/2021:01:46:04 +0000] "GET /favicon.ico HTTP/1.1" 404 555 "http://192.168.207.137/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.131 Safari/537.36 Edg/92.0.902.67" "-"
192.168.207.137 - - [13/Aug/2021:01:46:15 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.61.1" "-"
查看容器pid
USER PID PPID %CPU ELAPSED TTY TIME COMMAND
root 1 0 0.000 8m36.799916878s ? 0s nginx: master process nginx -g daemon off;
nginx 31 1 0.000 8m35.800072169s ? 0s nginx: worker process
nginx 32 1 0.000 8m35.800114617s ? 0s nginx: worker process
nginx 33 1 0.000 8m35.800158776s ? 0s nginx: worker process
nginx 34 1 0.000 8m35.800190938s ? 0s nginx: worker process
上传镜像
[root@hzy ~]# docker login
Username: 18463751776
Password:
Login Succeeded!
[root@hzy ~]# docker tag docker.io/library/1228322088/test:nginx 1228322088/test:nginx
[root@hzy ~]# docker push 18463751776/test:nginx
Getting image source signatures
Copying blob ca4de55a7918 skipped: already exists
Copying blob 0d97d41c4cc9 skipped: already exists
Copying blob 17a18be5dbcf skipped: already exists
Copying blob 79409a31937f skipped: already exists
Copying blob 814bff734324 [--------------------------------------] 0.0b / 0.0b
Copying config bde40dcb22 done
Writing manifest to image destination
Storing signatures
授权文件
podman login 登录，默认授权文件位于中${XDG_RUNTIME_DIR}/containers/auth.json
[root@hzy ~]# docker login
Authenticating with existing credentials...
Existing credentials are valid. Already logged in to docker.io
[root@hzy ~]# cat /run/user/0/containers/auth.json
{
"auths": {
"docker.io": {
"auth": "**************"
}
}
}
使用卷
容器与root用户一起运行，则root容器中的用户实际上就是主机上的用户。UID/GID1是在/etc/subuid和/etc/subgid等用户映射中指定的第一个UID/GID。如果普通用户的身份从主机目录挂载到容器中，并在该目录中以root用户身份创建文件，则会看到它实际上是你的用户在主机上拥有的
[root@hzy ~]$ docker run -it -v /tmp/root:/root httpd /bin/sh
# cd /root
# touch 111
# ls -l
total 0
-rw-r--r--. 1 root root 0 Aug 13 03:19 111
[root@hzy ~]# ll /tmp/root/
total 0
-rw-r--r--. 1 root root 0 Aug 13 11:19 111
--userns=keep-id参数，以确保用户被映射到容器内自己的UID和GID
[root@hzy ~]$ docker run -it --rm -v /tmp/root:/root --userns=keep-id httpd /bin/sh
$ whoami
root
$ touch 2222
$ ls -l
total 0
-rw-r--r--. 1 root root 0 Aug 13 03:23 111
-rw-r--r--. 1 root root 0 Aug 13 03:23 2222
[root@hzy ~]# ll /tmp/root/
total 0
-rw-r--r--. 1 root root 0 Aug 13 11:23 111
-rw-r--r--. 1 root root 0 Aug 13 11:23 2222
使用普通用户映射容器端口时会报“ permission denied”的错误
[root@hzy ~]$ docker run -d -p 80:80 httpd
Error: rootlessport cannot expose privileged port 80, you can add 'net.ipv4.ip_unprivileged_port_start=80' to /etc/sysctl.conf (currently 1024), or choose a larger port number (>= 1024): listen tcp 0.0.0.0:80: bind: permission denied
普通用户可以映射>= 1024的端口
[root@hzy ~]$ docker run -d -p 1024:80 httpd
0643591b2ca22c826f0945a58807a30a83cd0dedfe9daccd5dbc0efdab1c2c9f
[root@hzy ~]$ ss -anlt
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 *:1024 *:*
LISTEN 0 128 [::]:22 [::]:*
配置echo ‘net.ipv4.ip_unprivileged_port_start=80’ >> /etc/sysctl.conf后可以映射大于等于80的端口
[root@hzy user]# echo 'net.ipv4.ip_unprivileged_port_start=80' >> /etc/sysctl.conf
[root@hzy user]# sysctl -p
net.ipv4.ip_unprivileged_port_start = 80
[root@hzy ~]$ docker run -d -p 80:80 httpd
409221aa479316a50f43a074b7234daa46625beaea32e0eccc819d033b0b33aa
[root@hzy ~]$ ss -anlt
State Recv-Q Send-Q Local Address:Port Peer Address:Port Process
LISTEN 0 128 0.0.0.0:22 0.0.0.0:*
LISTEN 0 128 *:1024 *:*
LISTEN 0 128 *:80 *:*
LISTEN 0 128 *:81 *:*
LISTEN 0 128 [::]:22 [::]:*
普通用户使用的配置
在允许没有root特权的用户运行podman之前，管理员必须需要安装或构件podman并完成以下配置
在允许没有特殊权限的用户运行podman之前，管理员必须需要安装或构件podman并完成以下配置
cgroup V2Linux内核功能允许用户限制普通用户容器可以使用的资源，如果使用cgroup V2启用了运行Podman的Linux发行版，则可能需要更改默认的OCI运行时。某些较旧的版本runc不适用于cgroup V2，必须切换到备用OCI运行时crun。
[root@hzy ~]# rpm -aq| grep crun
crun-0.18-2.module_el8.4.0+830+8027e1c4.x86_64
可以使用--runtime选项在命令行中打开对cgroup V2的替代OCI运行时支持
podman --runtime crun
或者修改containers.conf文件
[root@hzy ~]# vim /usr/share/containers/containers.conf
……
runtime = "crun"
……
[root@hzy ~]# docker inspect nginx | grep crun
"OCIRuntime": "crun",
"crun",
安装slirp4netns
slirp4nets包为普通用户提供一种网络模式
[root@hzy ~]# rpm -qa | grep slirp4netns
slirp4netns-1.1.8-1.module_el8.4.0+641+6116a774.x86_64
安装fuse-overlayfs
在普通用户环境中使用Podman时，建议使用fuse-overlayfs而不是VFS文件系统，至少需要版本0.7.6
[root@hzy ~]# rpm -qa | grep fuse-overlayfs
fuse-overlayfs-1.4.0-3.module_el8.4.0+830+8027e1c4.x86_64
配置storage.conf文件
[root@hzy ~]# vim /etc/containers/storage.conf
……
driver = "overlay"
……
mount_program = "/usr/bin/fuse-overlayfs"
……
/etc/subuid和/etc/subgid配置
podman要求运行它的用户在/etc/subuid和/etc/subgid文件中列出一系列UID，shadow-utils或newuid包需要提供这些文件
[root@hzy ~]# rpm -qa| grep shadow-util
shadow-utils-4.6-12.el8.x86_64
可以在/etc/subuid和/etc/subgid查看，每个用户的值必须唯一且没有任何重叠
[root@hzy ~]# useradd ha
[root@hzy ~]# cat /etc/subuid
ha:100000:65536
该文件的格式为USERNAME:UID:RANGE
- 在/etc/passwd或个体pwent中列出用户名
- 为用户分配的初始UID
- 为用户分配的UID范围的大小
用户的配置文件
container.conf
podman读取顺序
- /usr/share/containers/containers.conf
- /etc/containers/containers.conf
- ~/.configg/containers/containers.conf
storage.conf
podman读取顺序
- /etc/containers/storage.conf
- ~/.configg/containers/storage.conf
在普通用户中这些字段默认
runroot = "/run/containers/storage"
# Primary Read/Write location of container storage
graphroot = "/var/lib/containers/storage"
# Storage path for rootless users
#
# rootless_storage_path = "$HOME/.local/share/containers/storage"
registries.conf
podman的读取顺序
- /etc/containers/registries.conf
- /etc/containers/registries.d/*
- ~/.config/containers/registries.conf
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