【ssh】What exactly does `ssh-keygen -A` do?

关于host key 

# vim /etc/rc.d/init.d/sshd

condrestart是conditional restart的意思。

如果服务当前已经是运行的话，它可以重启这个服务，但是如果服务没有运行，condrestart是无法启动这个服务的，而restart都可以。

What exactly does `ssh-keygen -A` do?

https://stackoverflow.com/questions/48983917/what-exactly-does-ssh-keygen-a-do

HOST KEY

https://www.ssh.com/ssh/host-key

explainshell.com

https://www.explainshell.com/explain?cmd=ssh-keygen+-A

ssh-keygen 中文手册

http://www.jinbuguo.com/openssh/ssh-keygen.html

sshd_config 中文手册

http://www.jinbuguo.com/openssh/sshd_config.html