CentOS - Jul 2006 - Problem with CentOS 4.3 and ldap

I currently have a server with centos 4.3 setup to do email.  I use
sendmail as the receiving agent and Dovecot as the pop/imap server.  Users
authenticate off of a openldap server.  Under a light load things appear
to work fine.  However under a moderately heavy load connections are left
open in a waiting state.  This causes some email to bounce with user
unknown, users authentications fails with bad username/password all with
valid accounts.

I am trying to figure out what the cause is to fix it but with out
success.  By restarting ldap and the ldap server I can minimize the
problem because the connections get reset.  I find nothing when I google
on the subject.  I don't believe this is a problem with the ldap server
because I have a Fedora core machine using it without problems.

Any help or ideas on how to track down the problem would be appreciated.

Myron Williams

On Wed, 12 Jul 2006, Myron Williams wrote:
> I currently have a server with centos 4.3 setup to do email.  I use 
> sendmail as the receiving agent and Dovecot as the pop/imap server.  
> Users authenticate off of a openldap server.  Under a light load 
> things appear to work fine.  However under a moderately heavy load 
> connections are left open in a waiting state.  This causes some 
> email to bounce with user unknown, users authentications fails with 
> bad username/password all with valid accounts.
> 
> I am trying to figure out what the cause is to fix it but with out 
> success.  By restarting ldap and the ldap server I can minimize the 
> problem because the connections get reset.  I find nothing when I 
> google on the subject.  I don't believe this is a problem with the 
> ldap server because I have a Fedora core machine using it without 
> problems.
Are you running nscd on the client side?

Have you tried bumping the slapd cache on the server side? (The config 
directive for doing so is specific to the database backend you're 
using.)

-- 
Paul Heinlein <> heinlein at madboa.com <> www.madboa.com