Slow password authentication

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Dear Group,

One of our servers takes an age to verify the password when logging in
using ssh.  The conection and prompt for username is almost instantaneous,
but then it seems to take about 20 seconds for the password to be checked.
After this the shell is just as quick as normal.

I have googled about this and all the problems seem to be with a slow
initial connection because of failing reverse dns lookups, but this is not
our problem.

The only think I can think is that the pasword checking is a low system
priority, and our sever is very very busy.  Therefore, I could renice it's
priority, but I think this would be a bit of a Kludge if there is a more
elegant solution.

any ideas?

Gareth Ansell

Re: Slow password authentication

On Mon, 20 Oct 2003 14:41:56 +0100, Gareth Ansell wrote:

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try a different network card driver. Im not sure about this, but my server
(redhat 9.0) had a harddisk failure so i had to reinstall the system. the
only differnence that i know of from the old config is my network card
driver, and it takes like two secs now to login, and maybe 15 before...


Re: Slow password authentication

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Did you check forward lookups too?

On the server, do a reverse lookup of the IP to the name, then do a
forward lookup of that name to an IP address.

Also, try running the server in debug name (eg "sshd -ddd -p 2022") and
see what it's doing when the client hangs.

Darren Tucker (dtucker at
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    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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