podman简介与安装与常用基础命令

podman简介与安装与常用基础命令

1 podman简介

Podman(Pod Manager)是一个功能齐全的容器引擎，是一个简单的无守护程序工具。Podman提供了一个与Docker-CLI类似的命令行，可以轻松地从其他容器引擎过渡，并允许管理Pod、容器和图像。简单地说： alias docker=podman 。大多数Podman命令都可以作为普通用户运行，而不需要额外的权限。

Podman在内部使用Buildah(1)创建容器映像。这两个工具共享图像(而不是容器)存储，因此每个工具都可以使用或操作对方创建的图像(但不能操作容器)。

标志的默认设置在中定义 containers.conf 。远程连接的大多数设置都使用服务器的tainers.conf，手册页中记录的情况除外。

2：podman与docker的差别

dockers在实现CRI的时候，它需要一个守护进程，以root权限运行这样会带来安全隐患，而podman不需要守护进程和root权限。
在docker的运行体系中，需要多个daemon才能调用到OCI的实现RunC。
在容器管理的链路中，Docker Engine的实现就是dockerd
daemon，它在linux中需要以root运行，dockerd调用containerd，containerd调用containerd-shim，然后才能调用runC。顾名思义shim起的作用也就是“垫片”，避免父进程退出影响容器的运行

3：安装podman与配置

安装podman

[root@localhost ~]# yum -y install podman

配置podman

[root@localhost ~]# vim /etc/containers/registries.conf
# unqualified-search-registries = ["registry.fedoraproject.org", "registry.access.redhat.com", "registry.centos.org", "docker.io"]unqualified-search-registries = ["docker.io"]
[[registry]]
prefix = "docker.io"
location = "wlfs9l74.mirror.aliyuncs.com"

4 podman容器常用基础命令

podman run

创建并启动容器

[root@localhost ~]# podman run --name httpd busybox:latest

start启动容器

[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED             STATUS            PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          About a minute ago  Up 3 seconds ago              httpd

ps 查看容器

[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED         STATUS             PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          12 seconds ago  Up 12 seconds ago              httpd

stop 停止容器

[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED         STATUS             PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          12 seconds ago  Up 12 seconds ago              httpd
[root@localhost ~]# podman stop httpd
[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED         STATUS                      PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          41 seconds ago  Exited (137) 8 seconds ago              httpd

restart 重启容器

[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED        STATUS                 PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          2 minutes ago  Up About a minute ago              httpd
[root@localhost ~]# podman  restart httpd
[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED        STATUS           PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          2 minutes ago  Up 1 second ago              httpd

attch 进入容器

[root@localhost ~]# podman attach httpd
/ #

exec 进入容器

[root@localhost ~]# podman exec -it httpd /bin/sh
/ #

rm 删除容器

[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE                             COMMAND     CREATED        STATUS            PORTS       NAMES
d36984b8d048  docker.io/library/busybox:latest  sh          8 minutes ago  Up 2 minutes ago              httpd
[root@localhost ~]# podman rm -f httpd
[root@localhost ~]# podman ps -a
CONTAINER ID  IMAGE       COMMAND     CREATED     STATUS      PORTS       NAMES

logs 查看日志

[root@localhost ~]# podman logs httpd

5：podman镜像常用基础命令

search 检索镜像

[root@localhost ~]# podman search httpd
NAME                                             DESCRIPTION
docker.io/library/httpd                          The Apache HTTP Server Project
docker.io/clearlinux/httpd                       httpd HyperText Transfer Protocol (HTTP) server program with the benefits of Clear Linux OS
docker.io/centos/httpd-24-centos7                Platform for running Apache httpd 2.4 or building httpd-based application

获取镜像

[root@localhost ~]# podman pull centos
Resolved "centos" as an alias (/etc/containers/registries.conf.d/000-shortnames.conf)
Trying to pull quay.io/centos/centos:latest...
Getting image source signatures
Copying blob 7a0437f04f83 done
Copying config 300e315adb done
Writing manifest to image destination
Storing signatures
300e315adb2f96afe5f0b2780b87f28ae95231fe3bdd1e16b9ba606307728f55
[root@localhost ~]# podman images
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

images 列出镜像

[root@localhost ~]# podman images
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

image ls 列出镜像

quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

rmi 删除镜像

[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
docker.io/ningnoob/ceshi   g1          beae173ccac6  7 months ago   1.46 MB
localhost/ningnoob/ceshi   c1          beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB
[root@localhost ~]#
[root@localhost ~]# podman rmi  localhost/ningnoob/ceshi:c1
Untagged: localhost/ningnoob/ceshi:c1
[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
docker.io/ningnoob/ceshi   g1          beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

image rm 删除镜像

[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
docker.io/ningnoob/ceshi   g1          beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB
[root@localhost ~]# podman image rm docker.io/ningnoob/ceshi:g1
Untagged: docker.io/ningnoob/ceshi:g1
[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

tag 标记本地镜像，将其归入某一仓库。

[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB
[root@localhost ~]#
[root@localhost ~]# podman tag docker.io/library/busybox:latest docker.io/ningnoob/ceshi:s1
[root@localhost ~]# podman images
REPOSITORY                 TAG         IMAGE ID      CREATED        SIZE
docker.io/library/busybox  latest      beae173ccac6  7 months ago   1.46 MB
docker.io/ningnoob/ceshi   s1          beae173ccac6  7 months ago   1.46 MB
quay.io/centos/centos      latest      300e315adb2f  20 months ago  217 MB

login 登录到一个镜像仓库

[root@localhost ~]# podman login
Username: ningnoob
Password:
Login Succeeded!

push 上传镜像

[root@localhost ~]# podman push docker.io/ningnoob/ceshi:s1
Getting image source signatures
Copying blob 01fd6df81c8e skipped: already exists
Copying config beae173cca done
Writing manifest to image destination
Storing signatures