There are several possible causes ssh logins to be slow. What often happens is because the ssh service is enabled by default dnslookup. So ssh to reverse dns of the ip address ssh client first. If the dns on the target machine has not be set then this will cause a delay between login prompts to input a password.

The solution is, the dns settings on the machine the ssh server. Able to add a dns server entry in / etc / resolv.conf or add a hosts table in / etc / hosts. And it could also turn off the feature dnslookup on sshd configuration. You do this by adding "UseDNS no" in / etc / ssh / sshd_config.

(on Server)

# vim / etc / ssh / sshd_config

UseDNS no

press ESC

type :wq

# service sshd restart