sshd启动报错解决：sshd re-exec requires execution with an absolute path

# sudo /usr/sbin/sshd
以下报错：
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
Missing privilege separation directory: /run/sshd

解决：
# sudo ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key
# sudo ssh-keygen -t ecdsa -f  /etc/ssh/ssh_host_ecdsa_key
# sudo ssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key