一、Containerd 镜像操作
1 基本参数
[root@ecs-65685 ~]# ctr c
NAME:
ctr containers - manage containers
USAGE:
ctr containers command [command options] [arguments...]
COMMANDS:
create create container
delete, del, remove, rm delete one or more existing containers
info get info about a container
list, ls list containers
label set and clear labels for a container
checkpoint checkpoint a container
restore restore a container from checkpoint
OPTIONS:
--help, -h show help2 镜像操作
在containerd中拉取docker的相关镜像也需要补全。
containerd支持oci标准的镜像，所以可以直接使用docker官方或dockerfile构建的镜像。
--platform 选项指定对应平台的镜像。当然对应的也有推送镜像的命令 ctr image push，如果是私有镜像则在推送的时候可以通过 --user 来自定义仓库的用户名和密码。
拉取镜像添加了--all-platforms会将所有平台都下载下来（amd64 、arm、386 、ppc64le ），否则默认下载当前平台。
拉取镜像可以使用 ctr image pull 来完成，比如拉取 Docker Hub 官方镜像 nginx:alpine，需要注意的是镜像地址需要加上 docker.io Host 地址。
ctr i pull docker.io/library/nginx:alpine --all-platforms3 查看镜像
查看镜像可以使用 i 或者image
-q 只打印镜像名称
ctr i ls
ctr i ls -q4 检测本地镜像
[root@ecs-65685 ~]# ctr image check
REF TYPE DIGEST STATUS SIZE UNPACKED
docker.io/library/nginx:alpine application/vnd.docker.distribution.manifest.list.v2+json sha256:b87c350e6c69e0dc7069093dcda226c4430f3836682af4f649f2af9e9b5f1c74 complete (7/7) 9.7 MiB/9.7 MiB true主要查看其中的 STATUS，complete 表示镜像是完整可用的状态。
5 tag重新打标签
[root@ecs-65685 ~]# ctr i tag docker.io/library/nginx:alpine docker.io/library/nginx:nginxxyz
docker.io/library/nginx:nginxxyz
[root@ecs-65685 ~]# ctr i ls -q
docker.io/library/nginx:alpine
docker.io/library/nginx:nginxxyz # 新增tag6 删除镜像
使用：delete, del, remove, rm remove one or more images by reference。都可以进行删除。
[root@ecs-65685 ~]# ctr i rm docker.io/library/nginx:nginxxyz
docker.io/library/nginx:nginxxyz
[root@ecs-65685 ~]# ctr i ls -q
docker.io/frps9/tools:SynologyNAS
docker.io/library/nginx:alpine7 mount镜像
mount镜像实际上将镜像中的文件，挂载到宿主机的目录中去。
mount参数系统为只读状态，只可以读取，不可以写入数据。
使用--rw Enable write support on the mount 可以开启只读。
[root@ecs-65685 ~]# mkdir /home/xyz
[root@ecs-65685 ~]# ctr i ls -q
docker.io/library/nginx:alpine
[root@ecs-65685 ~]# ctr i mount docker.io/library/nginx:alpine /home/xyz/
sha256:26bec62cc7fc1f93f810d51c3f51291dae2d0f9e192e054cc61d1914365003d8
/home/xyz/
[root@ecs-65685 ~]# ls /home/xyz
bin docker-entrypoint.d etc lib mnt proc run srv tmp var
dev docker-entrypoint.sh home media opt root sbin sys usrmount卸载
[root@ecs-65685 ~]# ctr i unmount /home/xyz
/home/xyz
[root@ecs-65685 ~]# ls /home/xyz8 推送镜像
[root@ecs-65685 ~]# ctr i push -k docker.io/library/nginx:alpine
index-sha256:b87c350e6c69e0dc7069093dcda226c4430f3836682af4f649f2af9e9b5f1c74: waiting |--------------------------------------|
elapsed: 0.1 s total: 0.0 B (0.0 B/s)
ctr: content digest sha256:36f21d30317cff60a6ab8328cca93dbe554020ba0320c78e964040512d0f27a0: not found跳过ssl验证--skip-verify， -k skip SSL certificate validation。
9 导入导出
import
export
默认export导出的为OCI tar，只要我们容器支持OCI，基本上都是可以使用的
同时导出可以使用--platform导出其它平台的(例如arm)
--all-platforms为导出所有平台
[root@ecs-65685 xyz]# ls
[root@ecs-65685 xyz]# ctr i ls -q
docker.io/library/nginx:alpine
[root@ecs-65685 xyz]# ctr i export --all-platforms nginx.tar docker.io/library/nginx:alpine
[root@ecs-65685 xyz]# ctr i export nginx_i4t.com.tar docker.io/library/nginx:alpine
[root@ecs-65685 xyz]# ls
nginx_i4t.com.tar nginx.tar
[root@ecs-65685 xyz]#
[root@ecs-65685 xyz]# ctr i rm docker.io/library/nginx:alpine
docker.io/library/nginx:alpine
[root@ecs-65685 xyz]# ctr i import nginx.tar
unpacking docker.io/library/nginx:alpine (sha256:b87c350e6c69e0dc7069093dcda226c4430f3836682af4f649f2af9e9b5f1c74)...done
[root@ecs-65685 xyz]# ctr i ls -q
docker.io/library/nginx:alpine二、Containerd 容器操作
1 基本参数
[root@ecs-65685 ~]# ctr c create -h
NAME:
ctr containers create - create container
USAGE:
ctr containers create [command options] [flags] Image|RootFS CONTAINER [COMMAND] [ARG...]
OPTIONS:
--snapshotter value snapshotter name. Empty value stands for the default value. [$CONTAINERD_SNAPSHOTTER]
--snapshotter-label value labels added to the new snapshot for this container.
--config value, -c value path to the runtime-specific spec config file
--cwd value specify the working directory of the process
--env value specify additional container environment variables (e.g. FOO=bar)
--env-file value specify additional container environment variables in a file(e.g. FOO=bar, one per line)
--label value specify additional labels (e.g. foo=bar)
--mount value specify additional container mount (e.g. type=bind,src=/tmp,dst=/host,options=rbind:ro)
--net-host enable host networking for the container
--privileged run privileged container
--read-only set the containers filesystem as readonly
--runtime value runtime name (default: "io.containerd.runc.v2")
--runtime-config-path value optional runtime config path
--tty, -t allocate a TTY for the container
--with-ns value specify existing Linux namespaces to join at container runtime (format '<nstype>:<path>')
--pid-file value file path to write the task's pid
--gpus value add gpus to the container
--allow-new-privs turn off OCI spec's NoNewPrivileges feature flag
--memory-limit value memory limit (in bytes) for the container (default: 0)
--device value file path to a device to add to the container; or a path to a directory tree of devices to add to the container
--cap-add value add Linux capabilities (Set capabilities with 'CAP_' prefix)
--cap-drop value drop Linux capabilities (Set capabilities with 'CAP_' prefix)
--seccomp enable the default seccomp profile
--seccomp-profile value file path to custom seccomp profile. seccomp must be set to true, before using seccomp-profile
--apparmor-default-profile value enable AppArmor with the default profile with the specified name, e.g. "cri-containerd.apparmor.d"
--apparmor-profile value enable AppArmor with an existing custom profile
--rdt-class value name of the RDT class to associate the container with. Specifies a Class of Service (CLOS) for cache and memory bandwidth management.
--rootfs use custom rootfs that is not managed by containerd snapshotter
--no-pivot disable use of pivot-root (linux only)
--cpu-quota value Limit CPU CFS quota (default: -1)
--cpu-period value Limit CPU CFS period (default: 0)
--rootfs-propagation value set the propagation of the container rootfs2 创建一个nginx容器
-n 指定命名空间
c 是简写 containers, c, container manage containers
create 创建容器
--net-host 使用宿主机网络
docker.io/xx/xxx:xxx 镜像地址
nginx 容器名称
ctr -n xyz c create --net-host docker.io/library/nginx:alpine nginx3 查看容器列表
[root@ecs-65685 ~]# ctr -n xyz c ls
CONTAINER IMAGE RUNTIME
nginx docker.io/library/nginx:alpine io.containerd.runc.v2
nginx1 docker.io/library/nginx:alpine io.containerd.runc.v24 只获取容器名称
[root@ecs-65685 ~]# ctr -n xyz c ls -q
nginx
nginx15 通过info参数查看容器的相关信息（类似于 docker inspect 功能）
ctr -n xyz c info nginx|less6 删除容器
[root@ecs-65685 ~]# ctr -n xyz c ls -q
nginx
nginx1
[root@ecs-65685 ~]# ctr -n xyz container rm nginx1
[root@ecs-65685 ~]# ctr -n xyz c ls -q
nginx除了使用 rm 子命令之外也可以使用 delete 或者 del 删除容器。
三、报错
ctr export导出或者import导入提示：ctr: content digest sha256:xxxxx: not found。
[root@ecs-65685 ~]# ctr image export --all-platforms nginx.tar docker.io/library/nginx:alpine
ctr: content digest sha256:36f21d30317cff60a6ab8328cca93dbe554020ba0320c78e964040512d0f27a0: not found2 现象：
直接导入某个镜像可能会出现类似于 ctr: content digest sha256:xxxxx: not found
解决办法：
删除下载好的镜像
拉取镜像、导出镜像时，都加上--all-platforms 时
再次import和export，不需要添加--all-platforms
四、Containerd-1.6.5 命名空间和task使用
https://www.cnblogs.com/huaxiayuyi/p/16790210.html
