Linux: Slow SSH Login – Login Lento con SSH

Thanks to http://www.hackosis.com/2007/12/15/linux-fix-slow-ssh-login/

The Problem:

By default, most SSH installations are set to do a reverse DNS lookup on any incoming connections. If the DNS server times out, or there is no record for your IP address, it can result in a very lengthy delay when logging into your Linux server via SSH.

The Solution:

There are about 3 different solutions to this problem.

1. Disable reverse lookup on the SSH server you are connecting to.Append
   UseDNS no
   UsePAM no

   to the /etc/ssh/sshd_config file on the server you are connecting to and restart the SSH daemon —

   /etc/init.d/sshd restart or /etc/init.d/ssh restart.

2. If you are connecting from a static IP, you may enter your host name in the /etc/hosts file.
3. Call your ISP and ask them to setup reverse hostnames for customer’s IP addresses.

And enjoy your non-delay SSH login for more info check out the sshd_config man page.