On Wed, Jan 13, 2010 at 3:34 PM, Andy Mastbaum <[log in to unmask]> wrote:
> Hello, all.
>
> I'm having a weird problem with my SL 5.3 login server. All of a sudden (and
> without me changing anything) logins over SSH are very, very slow -- up to a
> few minutes.
>
> Once users are logged in, everything is fast. This doesn't happen when I log
> in at the console, only over the network.
>
> I tried restarting every network service, rebuilding the NIS directory, and
> finally rebooting the server, and nothing has helped.

Most cases this is a reverse DNS problem. This can make things even
slower with good old NIS.

1) Check that the system is able to get DNS info correctly ( eg host
10.5.10.10 if the client comes from there and see where its stuck).
2) ssh -vvv is your friend on seeing if its client side.
3) sshd -p 2222 -ddd is your friend to see whats going on the server side.
4) if nscd is on. try turning it off and cleaning its cache.. that
will remove another vector.

Usually one can see pretty quick that its something like a lookup
failing or bad nscd cache etc.

> This is SL 5.3, Linux 2.6.18-128.1.10.el5 #1 SMP x86_64, user info is NIS
> (on the same server), and home directories are NFS-mounted, but NIS and NFS
> should be okay since local logins are fast. I'd think a problem with the
> NIC, but it's a nice Intel PRO/1000 and it's only the authentication that's
> slow.
>
> Any thoughts/suggestions are much appreciated... my users are getting pretty
> unhappy :(
>
> Thanks!
>
> Andy Mastbaum
> [log in to unmask]
>



-- 
Stephen J Smoogen.

Ah, but a man's reach should exceed his grasp. Or what's a heaven for?
-- Robert Browning