以 docker 安裝一個可以遠端 ssh 登入的 centos 7 image

以下紀錄如何產生一個基本的 docker image，安裝了 openssh-server 可以用 ssh 遠端登入。

設定 docker image 以及 openssh-server

docker run -it --name c1 centos:latest /bin/bash

安裝一些基本工具，以及 openssh-server

#yum provides ifconfig

yum install -y net-tools telnet iptables sudo initscripts
yum install -y passwd openssl openssh-server

測試 sshd

/usr/sbin/sshd -D
Could not load host key: /etc/ssh/ssh_host_rsa_key
Could not load host key: /etc/ssh/ssh_host_ecdsa_key
Could not load host key: /etc/ssh/ssh_host_ed25519_key

缺少了一些 key

ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
#直接 enter 即可

ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key
#直接 enter 即可

ssh-keygen -t ecdsa -f /etc/ssh/ssh_host_ecdsa_key -N ""

ssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key -N ""

修改 UsePAM 設定

vi /etc/ssh/sshd_config
# UsePAM yes 改成 UsePAM no
UsePAM no

再測試看看 sshd

/usr/sbin/sshd -D

修改 root 密碼

passwd root

離開 docker

exit

以 docker ps -l 找到剛剛那個 container 的 id

$ docker ps -l
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                     PORTS               NAMES
107fb9c3fc0d        centos:latest       "/bin/bash"         7 minutes ago       Exited (0) 2 seconds ago                       c1

將 container 存成另一個新的 image

docker commit 107fb9c3fc0d centosssh

以新的 image 啟動另一個 docker instance

docker run -d -p 10022:22 centosssh /usr/sbin/sshd -D

現在可以直接 ssh 登入新的 docker machine

ssh root@localhost -p 10022

如果遇到 Failed to get D-Bus connection: Operation not permitted 的問題：ref [原创] 解决 CentOS7 容器 Failed to get D-Bus connection: Operation not permitted

docker run -d -p 10022:22 -e "container=docker" --privileged=true -v /sys/fs/cgroup:/sys/fs/cgroup --name centos7test centosssh /usr/sbin/init

docker exec -it centos7test /bin/bash

gitolite 測試

在新的 docker 機器上安裝 gitolite 測試

yum install -y autoconf git

useradd git
passwd git

產生管理員的 key

ssh-keygen

Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Created directory '/root/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
01:93:46:03:17:6e:e2:06:ec:d6:07:db:2e:13:a3:92 root@1f01b0c5ad69
The key's randomart image is:
+--[ RSA 2048]----+
|    .oBo         |
| .   oo+         |
|  o o.o .        |
| . + *   .       |
|  o B o S        |
| o o =           |
|E . o .          |
| .   o           |
|                 |
+-----------------+

cp /root/.ssh/id_rsa.pub /home/git/admin.pub

以 scp 遠端測試 key

sshpass -p "password" scp -p -P 10022 git@localhost:/home/git/admin.pub .

在本機上安裝 gitolite

su - git

mkdir ~/bin

git clone git://github.com/sitaramc/gitolite

gitolite/install -ln ~/bin

把 admin.pub 放入 gitolite

gitolite setup -pk admin.pub

Initialized empty Git repository in /home/git/repositories/gitolite-admin.git/
Initialized empty Git repository in /home/git/repositories/testing.git/
WARNING: /home/git/.ssh missing; creating a new one
    (this is normal on a brand new install)
WARNING: /home/git/.ssh/authorized_keys missing; creating a new one
    (this is normal on a brand new install)

回到 root 身份

exit

以 git clone gitolite-admin 進行 local git 測試

mkdir test
cd test
git config --global user.email "charley@maxkit.com.tw"
git config --global user.name "charley"

git clone ssh://git@localhost/gitolite-admin

現在就可以利用 gitolite-admin 進行 git 帳號及 repo 維護

放入新的 user key: test.pub 放到 keydir 目錄中

git add keydir/test.pub

修改 conf/gitolite.conf

repo gitolite-admin
    RW+     =   admin
    RW+     =   test

repo testing
    RW+     =   admin
    RW+     =   test

將新的 test 增加到 gitolite-admin 裡面

git add keydir/test.pub
git add conf/gitolite.conf
git commit -m 'add test key'
git push origin master

也可以用遠端的方式存取 git

git clone ssh://git@localhost:10022/gitolite-admin

How to install Gitolite in CentOS 7

Linux 使用 Gitolite 架設 Git Server

使用Gitolite搭建Git服務器

gitolite basic administration

References

centos7中安裝一個可以ssh登陸的docker容器

Docker安裝SSH【Ubuntu、CentOS】