Docker¶

一、常用技巧¶

1.1 docker基础镜像¶

Alpine
Slim
Stretch
Buster
Jessie
Bullseye
windowsservercore

1.2 容器随机启动¶

# 1，容器启动时
docker run --restart=
  no           默认策略，在容器退出时不重启容器
  on-failure   在窗口非正常退出时（退出状态非0），才会重启容器
  on-failure:3 在容器非正常退出时重启容器，最多重启3次
  always       在容器退出时总是重启容器

# 2，容器运行中
docker update --restart=always <container id>

1.3 Centos¶

# 国内
yum install -y yum-utils
yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo

yum search docker-ce
yum info docker-ce
yum install docker-ce

mkdir -p /srv/lib/docker
ln -s /srv/lib/docker /var/lib/docker
systemctl enable docker
systemctl is-enabled docker
systemctl start docker
systemctl status docker

yum search docker-compose
yum install -y docker-compose

1.4 docker-compose¶

# down binary
# from https://docs.docker.com/compose/install/standalone/
curl -SL https://github.com/docker/compose/releases/download/v2.23.3/docker-compose-linux-x86_64 -o /usr/local/bin/docker-compose

# from epel
yum install -y docker-compose

二、CRI¶

	docker	ctr（containerd）	crictl（kubernetes）
查看运行的容器	docker ps	ctr task ls/ctr container ls	crictl ps
查看镜像	docker images	ctr image ls	crictl images
查看容器日志	docker logs	无	crictl logs
查看容器数据信息	docker inspect	ctr container info	crictl inspect
查看容器资源	docker stats	无	crictl stats
启动/关闭已有的容器	docker start/stop	ctr task start/kill	crictl start/stop
运行一个新的容器	docker run	ctr run	无（最小单元为 pod）
修改镜像标签	docker tag	ctr image tag	无
创建一个新的容器	docker create	ctr container create	crictl create
导入镜像	docker load	ctr image import	无
导出镜像	docker save	ctr image export	无
删除容器	docker rm	ctr container rm	crictl rm
删除镜像	docker rmi	ctr image rm	crictl rmi
拉取镜像	docker pull	ctr image pull	ctictl pull
推送镜像	docker push	ctr image push	无
在容器内部执行命令	docker exec	无	crictl exec

三、银河麒麟¶

通过二进制安装 docker

通过在线软件源和 rpm 包不能直接安装，那么只能选择通过编译安装了，去官网找了下发现提供有编译好的 docker 二进制包，直接下载二进制包安装吧，感谢 golang 的跨平台性。

3.1 安装条件¶

**64位**的操作系统

shell

# uname -p
aarch64

Linux 内核版本 ≥ 3.10

shell

# uname -r
4.19.90-17.ky10.aarch64

iptables 版本 ≥ 1.4

shell

# iptables --version
iptables v1.8.1 (legacy)

一个 ps 可执行文件，通常由 procps 或类似的包提供。

3.2 安装 Docker-ce¶

选择并下载 docker-ce 二进制包文件

官网下载地址：https://download.docker.com/linux/static/stable/aarch64/

shell

wget https://download.docker.com/linux/static/stable/aarch64/docker-20.10.7.tgz

解压下载好的压缩包

shell

tar -zxvf docker-20.10.7.tgz

移动解压出来的二进制文件到 /usr/bin 目录中

shell

mv docker/* /usr/bin/

测试启动

shell

dockerd

3.3 添加 systemd¶

添加 docker 的 systemd 服务脚本至 /usr/lib/systemd/system/

脚本参考自 https://github.com/docker/docker-ce

/usr/lib/systemd/system/docker.service

[Unit]
Description=Docker Application Container Engine
Documentation=https://docs.docker.com
After=network-online.target docker.socket firewalld.service containerd.service
Wants=network-online.target
Requires=docker.socket containerd.service

[Service]
Type=notify
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
ExecReload=/bin/kill -s HUP $MAINPID
TimeoutStartSec=0
RestartSec=2
Restart=always

# Note that StartLimit* options were moved from "Service" to "Unit" in systemd 229.
# Both the old, and new location are accepted by systemd 229 and up, so using the old location
# to make them work for either version of systemd.
StartLimitBurst=3

# Note that StartLimitInterval was renamed to StartLimitIntervalSec in systemd 230.
# Both the old, and new name are accepted by systemd 230 and up, so using the old name to make
# this option work for either version of systemd.
StartLimitInterval=60s

# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity

# Comment TasksMax if your systemd version does not support it.
# Only systemd 226 and above support this option.
TasksMax=infinity

# set delegate yes so that systemd does not reset the cgroups of docker containers
Delegate=yes

# kill only the docker process, not all processes in the cgroup
KillMode=process
OOMScoreAdjust=-500

[Install]
WantedBy=multi-user.target

根据 docker.service 中 Unit.After 需求添加 docker.socket 脚本至 /usr/lib/systemd/system/

脚本参考自 https://github.com/docker/docker-ce

/usr/lib/systemd/system/docker.socket

[Unit]
Description=Docker Socket for the API

[Socket]
# If /var/run is not implemented as a symlink to /run, you may need to
# specify ListenStream=/var/run/docker.sock instead.
ListenStream=/run/docker.sock
SocketMode=0660
SocketUser=root
SocketGroup=docker

[Install]
WantedBy=sockets.target

注意：如果缺少该文件，启动 docker 时会报如下错误：

shell

# systemctl start docker
Failed to start docker.service: Unit docker.socket not found.

根据 docker.service 中 Unit.After 需求添加 containerd.service 脚本至 /usr/lib/systemd/system/

脚本参考自 https://github.com/containerd/containerd

/usr/lib/systemd/system/containerd.service

# Copyright The containerd Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

[Unit]
Description=containerd container runtime
Documentation=https://containerd.io
After=network.target local-fs.target

[Service]
ExecStartPre=-/sbin/modprobe overlay
ExecStart=/usr/local/bin/containerd

Type=notify
Delegate=yes
KillMode=process
Restart=always
RestartSec=5
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
LimitNPROC=infinity
LimitCORE=infinity
LimitNOFILE=infinity
# Comment TasksMax if your systemd version does not supports it.
# Only systemd 226 and above support this version.
TasksMax=infinity
OOMScoreAdjust=-999

[Install]
WantedBy=multi-user.target

注意：如果缺少该文件，启动 docker 时会报如下错误：

shell

# systemctl restart docker
Failed to restart docker.service: Unit containerd.service not found.

重载 systemd 配置文件

shell

systemctl daemon-reload

创建 docker 组

shell

groupadd docker

如不创建 docker 组在通过 systemctl 启动时会报错如下

systemctl status docker

Dependency failed for Docker Application Container Engine.
Job docker.service/start failed with result 'dependency'.

启动 docker 服务

shell

systemctl start docker
systemctl enable docker

修改 docker 配置文件并查看安装好的 docker 基本信息

在 /etc/docker/daemon.json 中添加如下内容：

/etc/docker/daemon.json

{
    "graph": "/data/docker",
    "storage-driver": "overlay2",
    "exec-opts": [
        "native.cgroupdriver=systemd"
    ],
    "registry-mirrors": [
        "https://t5t8q6wn.mirror.aliyuncs.com"
    ],
    "bip": "172.8.94.1/24"
}

重启 docker 服务
```
shell

systemctl restart docker
```
查看 docker info

四、常见问题¶

4.1 下载¶

vim /usr/lib/systemd/system/docker.service

[Service]

Environment="HTTP_PROXY=http://127.0.0.1:50081/"
Environment="HTTPS_PROXY=http://127.0.0.1:50081/"
Environment="NO_PROXY=localhost,127.0.0.1,.example.com"

systemctl restart docker

docker pull mongo:7.0.12