今天在檢查某一台 CentOS 7 主機的 message log，發現 sshd 在啟動的時候出現錯誤訊息

error: Could not load host key: /etc/ssh/ssh_host_dsa_key

 

不知為何莫名少了 dsa key

在 CentOS 7 下的 ssh-keygen 支援 -A 來自動建立缺少的 key type

$ ssh-keygen -A

ssh-keygen: generating new host keys: DSA

$ systemctl restart sshd
$ systemctl status sshd

Apr 08 16:13:15 localhost.localdomain systemd[1]: Started OpenSSH server daemon.
Apr 08 16:13:15 localhost.localdomain systemd[1]: Starting OpenSSH server daemon...
Apr 08 16:13:15 localhost.localdomain sshd[2767]: Server listening on 0.0.0.0 port 22.
Apr 08 16:13:15 localhost.localdomain sshd[2767]: Server listening on :: port 22.

 

搞定！

Could not load host key ssh-keygen -A sshd