SSH Login delay

[gboyce at badbelly.com (Gregory Boyce)]

On Tue, 2005-02-15 at 16:14 -0500, David Cass wrote:
>My server is running Red-Hat 9, and when I access the server via SSH,
>the server responds immediately with a login request, and after I type
>in my login id the system responds immediately with "Sent username
>foo", and then there is a LONG pause (up to 30 seconds) before the
>system asks for my password.

A common cause of this is the server attempting to do a reverse DNS
lookup on the IP you're logging in from.  This can be quick unless the
nameservers authoritative for the netblock aren't reachable.

You can disable this by specifying "UseDNS no" in /etc/ssh/sshd_config.
Or you can fix the reverse DNS resolution.