RE: proftpd and sshd delays
Hi, thanks for the response.
As far as I know I'm not using any ident system on the server, although I'll
have to check. There are no packet filtering nor NAT systems between client
and server. Server does not drop outgoing connections.
I'm using passwd at the moment, but am trying to convert the system to LDAP
with a win2003 domain controller currently (the problems existed before this
attempt however).
I'll check the server on Monday when I go back to work and check up on your
suggestions.
Thanks for your help.
--James
-----Original Message-----
From: Mirko Parthey [mailto:mirko.parthey@informatik.tu-chemnitz.de]
Sent: Friday, 5 August 2005 3:42 PM
To: James Duff
Cc: debian-user@lists.debian.org
Subject: Re: proftpd and sshd delays
On Fri, Aug 05, 2005 at 03:13:01PM +0800, James Duff wrote:
> Both sshd, and proftpd are very slow to respond. I've noticed this in
> sshd under debian on previous versions and machines also. Sshd asks
> for a username almost immediately when I connect, but there is a
> substantial time before it asks for a password.
>
> Proftpd also has a significant delay before responding to login
> information.
Is there a packet filtering firewall or a NAT device between your client
machines and the server, or do your clients run a personal firewall software
which drops incoming connections? Or does your server machine drop outgoing
connections?
Your FTP and SSH servers might be configured to ask the client machine which
user issued the connection request. The "ident" protocol is used for this
purpose (sometimes also called "auth", which is a bit misnamed). If your
client machines ignore such connection attempts, instead of rejecting them,
this will cause the delays you observed.
You should be able to analyse this by running a packet sniffer such as
ethereal on the server side.
Another reason could be that the user lookup on the server itself takes too
long. Which user directory are you using - passwd, NIS, LDAP or something
else? If you don't know, please look in /etc/passwd for lines starting with
"+" (which would indicate you are using NIS), and post your
/etc/nsswitch.conf.
The strace tool, attached to a server process, might help diagnosing this
case.
Mirko
Reply to: