同一台电脑关于多个SSH KEY管理

使用环境:

• 关于同一台Mac电脑下使用多个SSH key 切换使用(或者多用户使用ssh提交代码)
• 既可以提交代码到github，也可以提交代码到oschina，提交的时候都走ssh协议，但是默认情况下只能有一个ssh key(~/ssh)

生成公钥、私钥

$ ssh-keygen -t rsa -C "your_github_email@example.com"
保存到 `~/.ssh/id_rsa_github`

$ ssh-keygen -t rsa -C "your_oschina_email@example.com"
保存到 `~/.ssh/id_rsa_oschina`

配置ssh代理

// 查看系统ssh-key代理
$ ssh-add -l

// 如果系统已经有ssh-key 代理 ,执行下面的命令可以删除
$ ssh-add -D

// 把 ~/.ssh 目录下的2个私钥添加的 ssh-agent
$ ssh-add ~/.ssh/id_rsa_github
$ ssh-add ~/.ssh/id_rsa_oschina

// 在 .ssh 目录创建 config 配置文件
$ vim ~/.ssh/config
#  github 配置
Host github
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_rsa_github

# oschina配置
Host oschina
    HostName git.oschina.net
    User git
    IdentityFile ~/.ssh/id_rsa_oschina

or

#aaa  (github 配置)
Host aaa
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_rsa_aaa

#bbb  (开源中国 配置)
Host bbb
    HostName git.oschina.net
    User git
    IdentityFile ~/.ssh/id_rsa_bbb

#ccc
........

记住上面一步 Host 里设置的别名

验证

// 查看ssh-key代理，会看到2条记录
$ ssh-add -l

// 访问github
$ ssh -T git@github.com
Hi 用户名! You have successfully authenticated, but GitHub does not provide shell access.

// 访问oschina
$ ssh -T git@git.oschina.net
Welcome to Git@OSC, 用户名!

or

// 访问aaa
$ ssh -T aaa

连接失败 (Permission denied (publickey).)

$ ~ ssh -T papillon        
The authenticity of host 'gitlab.com (52.167.219.168)' can't be established.
ECDSA key fingerprint is SHA256:HbW3g8zUjNSksFbqTiUWPWg2Bq1x8xdGUrliXFzSnUw.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'gitlab.com,52.167.219.168' (ECDSA) to the list of known hosts.
Authentication failed.

$ ~ ssh -T git@gitlab.com        
Permission denied (publickey).

ssh-agent

# 开启 agent
$ eval $(ssh-agent -s) ←┘
Agent pid 8428

# 添加 钥匙名
$ ssh-add ~/.ssh/id_rsa_github ←┘
Identity added: /c/Users/user/.ssh/id_rsa_github (/c/Users/user/.ssh/id_rsa_github)

# 查看 agent list
$ ssh-add -l ←┘
8428 SHA256:A9UcJMadwTpF7TvsT5LEXsSssTs5qehmV9Q2Q8Ntw3o /c/Users/user/.ssh/id_rsa_github (RSA)

# 不用时可以关闭 agent
$ eval $(ssh-agent -k) ←┘
Agent pid 8428 killed

原因是，我们自定义了 id_rsa_github 钥匙名，默认情况下，连接会搜索 id_rsa 钥匙名，所以这里会失败
可以通过 ssh -T -v git@github.com 了解连接失败的具体原因

还有一种简单的办法,直接删除id_rsa钥匙名，全部使用带有后缀的格式来写

$ .ssh ls
config              id_rsa.pub          id_rsa_gat.pub      id_rsa_papillon.pub
id_rsa              id_rsa_gat          id_rsa_papillon     known_hosts
$ .ssh rm id_rsa id_rsa.pub