3.5. 重启容器

因为 podman 不支持 --restart 选项,所以您可以将 podman 配置为 systemd 服务,如 使用 Podman 将容器移植到 systemd所述

3.5.1. 在 Podman 中使用 systemd 单元文件

默认情况下,Podman 为现有容器或 pod 生成一个单元文件。您可以使用 podman generate systemd --new 命令生成更多可移植的 systemd 单元文件。--new 标志指示 Podman 生成创建、启动和删除容器的单元文件。

  1. 从正在运行的 Red Hat Quay registry 创建 systemd 单元文件,如下所示:

    $ sudo podman generate systemd --new --files --name redis
    $ sudo podman generate systemd --new --files --name postgresql-quay
    $ sudo podman generate systemd --new --files --name quay
    $ sudo podman generate systemd --new --files --name postgresql-clairv4
    $ sudo podman generate systemd --new --files --name clairv4
  2. 将单元文件复制到 /usr/lib/systemd/system 中,以便以 root 用户身份安装它们:

    $ sudo cp -Z container-redis.service /usr/lib/systemd/system
    $ sudo cp -Z container-postgresql-quay.service /usr/lib/systemd/system
    $ sudo cp -Z container-quay.service /usr/lib/systemd/system
    $ sudo cp -Z container-postgresql-clairv4.service /usr/lib/systemd/system
    $ sudo cp -Z container-clairv4.service /usr/lib/systemd/system
  3. 重新载入 systemd Manager 配置:

    $ sudo systemctl daemon-reload
  4. 启用服务并在引导时启动它们:

    $ sudo systemctl enable --now container-redis.service
    $ sudo systemctl enable --now container-postgresql-quay.service
    $ sudo systemctl enable --now container-quay.service
    $ sudo systemctl enable --now container-postgresql-clairv4.service
    $ sudo systemctl enable --now container-clairv4.service

3.5.2. 启动、停止和检查服务的状态

  1. 检查 Quay 组件的状态:

    $ sudo systemctl status container-redis.service
    $ sudo systemctl status container-postgresql-quay.service
    $ sudo systemctl status container-quay.service
    $ sudo systemctl status container-postgresql-clairv4.service
    $ sudo systemctl status container-clairv4.service
  2. 停止 Quay 组件服务:

    $ sudo systemctl stop container-redis.service
    $ sudo systemctl stop container-postgresql-quay.service
    $ sudo systemctl stop container-quay.service
    $ sudo systemctl stop container-postgresql-clairv4.service
    $ sudo systemctl stop container-clairv4.service
  3. 启动 Quay 组件服务:

    $ sudo systemctl start container-redis.service
    $ sudo systemctl start container-postgresql-quay.service
    $ sudo systemctl start container-quay.service
    $ sudo systemctl start container-postgresql-clairv4.service
    $ sudo systemctl start container-clairv4.service

3.5.3. 重启后测试重启

配置并启用服务后,重启系统。系统重新启动后,请使用 podman ps 检查 Quay 组件的所有容器是否已重启:

$ sudo podman ps -a
CONTAINER ID  IMAGE                                       COMMAND         CREATED         STATUS             PORTS                   NAMES
4e87c7889246  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  19 seconds ago  Up 18 seconds ago  0.0.0.0:5432->5432/tcp  postgresql-quay
b8fbac1920d4  registry.redhat.io/rhel8/redis-6:1-110)          run-redis       19 seconds ago  Up 18 seconds ago  0.0.0.0:6379->6379/tcp  redis
d959d5bf7a24  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  18 seconds ago  Up 18 seconds ago  0.0.0.0:5433->5432/tcp  postgresql-clairv4
e75ff8651dbd  registry.redhat.io/quay/clair-rhel8:v3.4.0                  18 seconds ago  Up 17 seconds ago  0.0.0.0:8081->8080/tcp  clairv4

在本实例中,Quay 容器本身无法启动。这是因为,当在 Quay 中启用了安全扫描时,它会在启动时尝试连接到 Clair。但是,Clair 还没有完成初始化,因此无法接受连接,因此 Quay 会立即终止。要解决这个问题,您需要将 Quay 服务配置为依赖于 Clair 服务,如以下部分所示。

3.5.4. 配置 Quay 对 Clair 的依赖项

在 Quay 的 systemd 服务文件中,通过设置 After=container-clairv4.service 来对 [Unit] 部分中的 Clair 服务设置依赖项。要为 Clair 容器指定初始化时间,请在 [Service] 部分添加一个延迟,如 RestartSec=30。以下是在配置依赖 Clair 后修改的 Quay 文件的示例:

/usr/lib/systemd/system/container-quay.service

# container-quay.service
# autogenerated by Podman 2.0.5
# Tue Feb 16 17:02:26 GMT 2021

[Unit]
Description=Podman container-quay.service
Documentation=man:podman-generate-systemd(1)
Wants=network.target
After=container-clairv4.service

[Service]
Environment=PODMAN_SYSTEMD_UNIT=%n
Restart=on-failure
RestartSec=30
ExecStartPre=/bin/rm -f %t/container-quay.pid %t/container-quay.ctr-id
ExecStart=/usr/bin/podman run --conmon-pidfile %t/container-quay.pid --cidfile %t/container-quay.ctr-id --cgroups=no-conmon -d --rm -p 8080:8080 --name=quay -v /home/user1/quay/config:/conf/stack:Z -v /home/user1/quay/storage:/datastorage:Z registry.redhat.io/quay/quay-rhel8:v3.4.0
ExecStop=/usr/bin/podman stop --ignore --cidfile %t/container-quay.ctr-id -t 10
ExecStopPost=/usr/bin/podman rm --ignore -f --cidfile %t/container-quay.ctr-id
PIDFile=%t/container-quay.pid
KillMode=none
Type=forking

[Install]
WantedBy=multi-user.target default.target

更新 Quay 服务配置后,重启服务器并立即运行 podman ps

$ sudo podman ps -a
CONTAINER ID  IMAGE                                       COMMAND         CREATED         STATUS             PORTS                   NAMES
4e87c7889246  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  29 seconds ago  Up 28 seconds ago  0.0.0.0:5432->5432/tcp  postgresql-quay
b8fbac1920d4  registry.redhat.io/rhel8/redis-6:1-110)          run-redis       29 seconds ago  Up 28 seconds ago  0.0.0.0:6379->6379/tcp  redis
d959d5bf7a24  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  28 seconds ago  Up 28 seconds ago  0.0.0.0:5433->5432/tcp  postgresql-clairv4
e75ff8651dbd  registry.redhat.io/quay/clair-rhel8:v3.4.0                  28 seconds ago  Up 27 seconds ago  0.0.0.0:8081->8080/tcp  clairv4

最初,Quay 容器不可用,但当 RestartSec 延迟已过期后,它应该会启动:

$ sudo podman ps -a
CONTAINER ID  IMAGE                                       COMMAND         CREATED         STATUS             PORTS                   NAMES
4e87c7889246  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  35 seconds ago  Up 34 seconds ago  0.0.0.0:5432->5432/tcp  postgresql-quay
ab9f0e6ad7c3  registry.redhat.io/quay/quay-rhel8:v3.4.0   registry        3 seconds ago   Up 2 seconds ago   0.0.0.0:8080->8080/tcp  quay
b8fbac1920d4  registry.redhat.io/rhel8/redis-6:1-110)          run-redis       35 seconds ago  Up 34 seconds ago  0.0.0.0:6379->6379/tcp  redis
d959d5bf7a24  registry.redhat.io/rhel8/postgresql-13:1-109    run-postgresql  34 seconds ago  Up 34 seconds ago  0.0.0.0:5433->5432/tcp  postgresql-clairv4
e75ff8651dbd  registry.redhat.io/quay/clair-rhel8:v3.4.0                  34 seconds ago  Up 33 seconds ago  0.0.0.0:8081->8080/tcp  clairv4

Quay 容器的 CREATED 字段显示在创建时间时 30 秒差别,如服务定义中所示。

登录到 quay-server.example.com 中的 Red Hat Quay registry,并确保所有内容都已正确重启。