Ubuntu 22.04 Docker安装笔记

1、准备一台虚机

可以根据《VMware Workstation安装Ubuntu 22.04笔记》来准备虚拟机。完成后，根据需求安装必要的软件，并设置root权限进行登录。

sudo apt update
sudo apt install iputils-ping -y
sudo apt install vim -y

允许root ssh登录：
sudo passwd root
sudo vi /etc/ssh/sshd_config
...
#PermitRootLogin prohibit-password
PermitRootLogin yes <--新增配置
...
sudo /etc/init.d/ssh stop
sudo /etc/init.d/ssh start
sudo service ssh restart

其他相关信息：

root@host1:~# hostname
host1

root@host1:~# uname -a
Linux host1 5.15.0-117-generic #127-Ubuntu SMP Fri Jul 5 20:13:28 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
root@host1:~# cat /etc/*release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=22.04
DISTRIB_CODENAME=jammy
DISTRIB_DESCRIPTION="Ubuntu 22.04.4 LTS"
PRETTY_NAME="Ubuntu 22.04.4 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.4 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy
root@host1:~# 

root@host1:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:ba:cd:1a brd ff:ff:ff:ff:ff:ff
    altname enp2s0
    inet 10.0.20.61/24 brd 10.0.20.255 scope global ens32
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:feba:cd1a/64 scope link 
       valid_lft forever preferred_lft forever
3: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 00:0c:29:ba:cd:24 brd ff:ff:ff:ff:ff:ff
    altname enp2s1
    inet6 fe80::20c:29ff:feba:cd24/64 scope link 
       valid_lft forever preferred_lft forever

2、Docker安装

Docker是一个开源的软件平台，它允许你通过容器化技术来构建、测试和运行应用程序。容器化是一种轻量级、可移植的、自给自足的软件运行方式，它使得应用程序及其依赖项可以被打包在一起，从而简化了软件的部署和管理。

Docker为Ubuntu提供了一个官方的APT仓库，这使得在Ubuntu系统上安装Docker变得非常简单。以下是在Ubuntu 22.04上安装Docker的步骤：

更新包索引

更新本地包索引以确保安装的是最新版本的软件包。

root@host1:~# apt update

安装所需的软件包

root@host1:~# apt install -y apt-transport-https ca-certificates curl software-properties-common

apt-transport-https: 这个软件包提供了通过 HTTPS 协议获取软件包的能力。

ca-certificates: 包含用于验证 HTTPS 连接的证书。

curl: 是一个命令行工具和库，用于传输数据，支持多种协议，包括 HTTP、HTTPS 和 FTP。

software-properties-common: 包含用于添加和管理软件源的工具。

添加 Docker 的官方 GPG 密钥到 Ubuntu 系统

root@host1:~# curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg

root@host1:~# ls /usr/share/keyrings/docker-archive-keyring.gpg
/usr/share/keyrings/docker-archive-keyring.gpg
root@host1:~#

curl: 是一个命令行工具，用于从或向服务器传输数据。

-fsSL: 选项组合：

-f 或 -fail：服务器返回失败的HTTP状态码时不显示错误。

-s 或 --silent：静默或无输出模式。

-S 或 --show-error：在出现问题时显示错误。

-L 或 --location：跟随重定向。

https://download.docker.com/linux/ubuntu/gpg: 是 Docker 官方的 GPG 密钥的 URL。

|: 是管道操作符，将前一个命令的输出作为后一个命令的输入。

sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg: 这个命令使用 gpg 工具将通过管道接收到的密钥转换为二进制格式，并将其输出到指定的文件路径。

将 Docker 的官方软件源添加到 Ubuntu 的 APT 软件源列表中

root@host1:~# echo "deb [arch=amd64 signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

执行这个命令后，Docker 的官方软件源将被添加到您的系统软件源列表中，APT 将能够从这个源安装 Docker。

在 Ubuntu 系统中安装 Docker CE（社区版）及其命令行接口（CLI）和 containerd.io 容器运行时：

root@host1:~# apt update
root@host1:~# apt install -y docker-ce docker-ce-cli containerd.io
设置 Docker 服务在系统启动时自动启动

root@host1:~# systemctl enable docker
Synchronizing state of docker.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install enable docker
root@host1:~#
显示当前安装的 Docker 版本信息

root@host1:~# docker --version
Docker version 27.1.1, build 6312585

root@host1:~# systemctl status docker
● docker.service - Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
Active: active (running) since Tue 2024-08-06 02:27:10 UTC; 2min 49s ago
TriggeredBy: ● docker.socket
Docs: https://docs.docker.com
Main PID: 2050 (dockerd)
Tasks: 10
Memory: 22.0M
CPU: 321ms
CGroup: /system.slice/docker.service
└─2050 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock

Aug 06 02:27:09 host1 systemd[1]: Starting Docker Application Container Engine...
Aug 06 02:27:09 host1 dockerd[2050]: time="2024-08-06T02:27:09.804576515Z" level=info msg="Starting up"
Aug 06 02:27:09 host1 dockerd[2050]: time="2024-08-06T02:27:09.805423605Z" level=info msg="detected 127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf: /run/systemd/resolve/resolv.conf"
Aug 06 02:27:09 host1 dockerd[2050]: time="2024-08-06T02:27:09.886376001Z" level=info msg="Loading containers: start."
Aug 06 02:27:10 host1 dockerd[2050]: time="2024-08-06T02:27:10.259919206Z" level=info msg="Loading containers: done."
Aug 06 02:27:10 host1 dockerd[2050]: time="2024-08-06T02:27:10.278184800Z" level=info msg="Docker daemon" commit=cc13f95 containerd-snapshotter=false storage-driver=overlay2 version=27.1.1
Aug 06 02:27:10 host1 dockerd[2050]: time="2024-08-06T02:27:10.278390653Z" level=info msg="Daemon has completed initialization"
Aug 06 02:27:10 host1 dockerd[2050]: time="2024-08-06T02:27:10.319697168Z" level=info msg="API listen on /run/docker.sock"
Aug 06 02:27:10 host1 systemd[1]: Started Docker Application Container Engine.
root@host1:~#
测试 Docker 是否正确安装

root@host1:~# docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
c1ec31eb5944: Pull complete
Digest: sha256:1408fec50309afee38f3535383f5b09419e6dc0925bc69891e79d84cc4cdcec6
Status: Downloaded newer image for hello-world:latest

Hello from Docker!
This message shows that your installation appears to be working correctly.

To generate this message, Docker took the following steps:
1. The Docker client contacted the Docker daemon.
2. The Docker daemon pulled the "hello-world" image from the Docker Hub.
  (amd64)
3. The Docker daemon created a new container from that image which runs the
  executable that produces the output you are currently reading.
4. The Docker daemon streamed that output to the Docker client, which sent it
  to your terminal.
To try something more ambitious, you can run an Ubuntu container with:
$ docker run -it ubuntu bash

Share images, automate workflows, and more with a free Docker ID:
https://hub.docker.com/

For more examples and ideas, visit:
https://docs.docker.com/get-started/

root@host1:~#

3、Docker使用

3.1 docker pull 下载镜像

1、从Docker Hub（Docker的官方镜像仓库）下载标签为 22.04 的Ubuntu镜像：

root@host1:~# docker pull ubuntu:22.04
22.04: Pulling from library/ubuntu
3713021b0277: Pull complete 
Digest: sha256:340d9b015b194dc6e2a13938944e0d016e57b9679963fdeb9ce021daac430221
Status: Downloaded newer image for ubuntu:22.04
docker.io/library/ubuntu:22.04

2、列出本地的Docker镜像：

root@host1:~# docker images
REPOSITORY    TAG       IMAGE ID       CREATED         SIZE
ubuntu        22.04     8a3cdc4d1ad3   5 weeks ago     77.9MB
hello-world   latest    d2c94e258dcb   15 months ago   13.3kB

3.2 docker run 启动容器

在Docker中创建并启动一个名为 test1 的新容器，使用 ubuntu:22.04 镜像，并提供一个交互式的bash shell：

root@host1:~# docker run --name test1 -it ubuntu:22.04 /bin/bash
root@33d9582b76bf:/# exit
exit
root@host1:~#

-it：这是一个组合选项，-i 表示交互式，-t 表示分配一个伪终端。这个选项允许你与容器内的进程进行交互

/bin/bash：这是容器启动后要运行的命令，即启动bash shell

执行这个命令后，Docker会做以下几件事：

检查本地是否有 ubuntu:22.04 镜像，如果没有，它会从Docker Hub下载这个镜像。
使用这个镜像创建一个新的容器，命名为 test1。
启动容器，并提供一个交互式的bash shell，允许你执行命令和操作。
要退出终端，直接输入 exit。

启动容器，同时后台运行:

root@host1:~# docker run --name test2 -itd ubuntu:22.04 /bin/bash
13406586d37f4dceadf75d49643d401cbc806d81e48a085f54969e279ab593ee

3.3 docker ps 列出容器

列出所有容器，包括正在运行的和已经停止的容器：

root@host1:~# docker ps -a
CONTAINER ID   IMAGE          COMMAND       CREATED              STATUS                       PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   About a minute ago   Up About a minute                      test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   23 minutes ago       Exited (137) 4 seconds ago             test1
6843deb526c2   hello-world    "/hello"      11 hours ago         Exited (0) 11 hours ago                great_booth
root@host1:~#

只列出正在运行的容器:

root@host1:~# docker ps 
CONTAINER ID   IMAGE          COMMAND       CREATED              STATUS              PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   About a minute ago   Up About a minute             test2
root@host1:~#

3.4 docker start启动已经停止的容器

root@host1:~# docker start test1
test1
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS         PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   2 minutes ago    Up 2 minutes             test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   24 minutes ago   Up 4 seconds             test1
root@host1:~# docker ps -a
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS                    PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   2 minutes ago    Up 2 minutes                        test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   24 minutes ago   Up 8 seconds                        test1
6843deb526c2   hello-world    "/hello"      11 hours ago     Exited (0) 11 hours ago             great_booth
root@host1:~#

3.5 docker stop 停止容器

root@host1:~# docker stop test1
test1

3.6 docker restart 重启容器

root@host1:~# docker restart test1
test1
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS         PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   8 minutes ago    Up 8 minutes             test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   30 minutes ago   Up 4 seconds             test1
root@host1:~#

docker start和docker restart区别：

docker start 仅用于启动已经停止的容器，不会重新初始化容器的启动命令。

docker restart 可以用于重启正在运行的容器，或者重新启动已经停止的容器，并且会重新执行容器的启动命令。

使用场景：

如果你需要重新激活一个已经停止的容器，并且希望它从停止时的状态继续运行，使用 docker start。

如果你需要重置容器的状态，或者容器需要在重启时重新加载配置或执行初始化命令，使用 docker restart。

3.7 docker attach进入容器

docker run -itd方式，启动容器会进入后台；或者docker start/restart，重新启动的容器也会进入后台。此时，要进入容器，可以使用docker attach，执行exit退出容器：

root@host1:~# docker attach test1
root@33d9582b76bf:/# 
root@33d9582b76bf:/# exit
exit
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   13 minutes ago   Up 13 minutes             test2
root@host1:~#

3.8 docker exec进入容器

root@host1:~# docker start test1
test1
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   20 minutes ago   Up 20 minutes             test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   42 minutes ago   Up 3 seconds              test1
root@host1:~# docker exec -it 33d9582b76bf /bin/bash
root@33d9582b76bf:/#     
root@33d9582b76bf:/# exit
exit
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   20 minutes ago   Up 20 minutes             test2
33d9582b76bf   ubuntu:22.04   "/bin/bash"   43 minutes ago   Up 42 seconds             test1
root@host1:~#

使用docker exec进入容器，如果从这个容器退出，容器不会停止。

3.9 docker rm 删除容器

root@host1:~# docker rm -f test1
test1
root@host1:~# docker ps -a
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS                    PORTS     NAMES
13406586d37f   ubuntu:22.04   "/bin/bash"   26 minutes ago   Up 26 minutes                       test2
6843deb526c2   hello-world    "/hello"      12 hours ago     Exited (0) 12 hours ago             great_booth
root@host1:~#

4、容器之间相互Ping通

1、进入容器test1/test2，并安装相应软件：

容器test1安装软件：
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
e6fb111b9b11   ubuntu:22.04   "/bin/bash"   3 seconds ago    Up 3 seconds              test1
13406586d37f   ubuntu:22.04   "/bin/bash"   30 minutes ago   Up 30 minutes             test2
root@host1:~# docker exec -it e6fb111b9b11 /bin/bash
root@e6fb111b9b11:/# ip a
bash: ip: command not found
root@e6fb111b9b11:/# apt update
root@e6fb111b9b11:/# apt install iproute2
root@e6fb111b9b11:/# apt install inetutils-ping -y

root@e6fb111b9b11:/# exit
exit

容器test2安装软件：
root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
e6fb111b9b11   ubuntu:22.04   "/bin/bash"   5 minutes ago    Up 5 minutes              test1
13406586d37f   ubuntu:22.04   "/bin/bash"   35 minutes ago   Up 35 minutes             test2
root@host1:~# 
root@host1:~# docker exec -it 13406586d37f /bin/bash
root@13406586d37f:/# apt update

2、查看容器ip地址信息，并相互ping

root@host1:~# docker ps
CONTAINER ID   IMAGE          COMMAND       CREATED          STATUS          PORTS     NAMES
e6fb111b9b11   ubuntu:22.04   "/bin/bash"   10 minutes ago   Up 10 minutes             test1
13406586d37f   ubuntu:22.04   "/bin/bash"   40 minutes ago   Up 40 minutes             test2

进入容器test1:
root@host1:~# docker exec -it e6fb111b9b11 /bin/bash
root@e6fb111b9b11:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
23: eth0@if24: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default 
    link/ether 02:42:ac:11:00:02 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 172.17.0.2/16 brd 172.17.255.255 scope global eth0
       valid_lft forever preferred_lft forever
root@e6fb111b9b11:/# 

进入容器test2:
root@host1:~# docker exec -it 13406586d37f /bin/bash
root@13406586d37f:/# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
15: eth0@if16: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default 
    link/ether 02:42:ac:11:00:03 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet 172.17.0.3/16 brd 172.17.255.255 scope global eth0
       valid_lft forever preferred_lft forever

容器test2 ping 容器test1:
root@e6fb111b9b11:/# ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2): 56 data bytes
64 bytes from 172.17.0.2: icmp_seq=0 ttl=64 time=0.061 ms
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.040 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.033 ms
^C--- 172.17.0.2 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.033/0.045/0.061/0.000 ms
root@e6fb111b9b11:/#