Fedora directory users - Jan 2008 - Random UID not found problem

Hi,
Some of our users get "UID xxxx not found"  message when they open a
new
terminal or run a rsh command, it appears a few times a day and  it is
mostly just annoying message because users can continue to work as
normal, however, sometimes It also causes  cron jobs to fail,
In system log, it shows,

crond(pam_unix)[9225]: could not identify user (from getpwnam(USERNAME))
crond[9225]: User not known to the underlying authentication module

We are using Fedora DS 1.0.4, and clients are RHEL 4.5 . This problem
started ever since we switched into LDAP three months ago.

Thanks

markwu@micron.com wrote:
>
> Hi,
> Some of our users get "UID xxxx not found"  message when they
open a
> new terminal or run a rsh command, it appears a few times a day and  
> it is mostly just annoying message because users can continue to work 
> as normal, however, sometimes It also causes  cron jobs to fail,
>
> In system log, it shows,
>
> crond(pam_unix)[9225]: could not identify user (from getpwnam(USERNAME))
> crond[9225]: User not known to the underlying authentication module
>
> We are using Fedora DS 1.0.4, and clients are RHEL 4.5 . This problem 
> started ever since we switched into LDAP three months ago.
>
Look at the DS access logs from around the time of the failure to see if 
you get a failed BIND or SEARCH attempt.
>
> Thanks
>
> ------------------------------------------------------------------------
>
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> Fedora-directory-users mailing list
> Fedora-directory-users@redhat.com
> https://www.redhat.com/mailman/listinfo/fedora-directory-users
>

We just found that all cron jobs at 0,10,20,30,50 every hour would fail
consistently and give the error in my original post, but any other
minutes all cron jobs are OK.
We are using nss_ldap_226-18 and crontabs-1.10-7. I will check if UID
not found problem occurs also at 10th minutes.
> _____________________________________________ 
> From: 	markwu  
> Sent:	Wednesday, January 30, 2008 2:42 PM
> To:	''fedora-directory-users@redhat.com''
> Subject:	Random UID not found problem
> 
> Hi,
> Some of our users get "UID xxxx not found"  message when they
open a
> new terminal or run a rsh command, it appears a few times a day and
> it is mostly just annoying message because users can continue to work
> as normal, however, sometimes It also causes  cron jobs to fail,
> In system log, it shows,
> 
> crond(pam_unix)[9225]: could not identify user (from
> getpwnam(USERNAME))
> crond[9225]: User not known to the underlying authentication module
> 
> We are using Fedora DS 1.0.4, and clients are RHEL 4.5 . This problem
> started ever since we switched into LDAP three months ago.
> 
> Thanks
>

We have found the problem is the overloading the master server, once we
switch client to use a consumer server as primary ldap server, all
problems are gone.
The Master has 16G RAM, two quad-core 3G CPU and it is binding to 400
client machines with 7000 TCP connections. I will try some performance
tuning.
> From: 	markwu  
> Sent:	Thursday, January 31, 2008 2:57 PM
> To:	''fedora-directory-users@redhat.com''
> Subject:	RE: Random UID not found problem
> 
> We just found that all cron jobs at 0,10,20,30,50 every hour would
> fail consistently and give the error in my original post, but any
> other minutes all cron jobs are OK.
> We are using nss_ldap_226-18 and crontabs-1.10-7. I will check if UID
> not found problem occurs also at 10th minutes.
> 
> _____________________________________________ 
> From: 	markwu  
> Sent:	Wednesday, January 30, 2008 2:42 PM
> To:	''fedora-directory-users@redhat.com''
> Subject:	Random UID not found problem
> 
> Hi,
> Some of our users get "UID xxxx not found"  message when they
open a
> new terminal or run a rsh command, it appears a few times a day and
> it is mostly just annoying message because users can continue to work
> as normal, however, sometimes It also causes  cron jobs to fail,
> In system log, it shows,
> 
> crond(pam_unix)[9225]: could not identify user (from
> getpwnam(USERNAME))
> crond[9225]: User not known to the underlying authentication module
> 
> We are using Fedora DS 1.0.4, and clients are RHEL 4.5 . This problem
> started ever since we switched into LDAP three months ago.
> 
> Thanks
>