[Samba] LDAP redudancy problem

[Alain.Gorlier at altissemiconductor.com]

Hi,

Redhat 4, Samba server 3.0.22.

We are testing LDAP redudancy. We have 2 LDAP servers.

If we stop LDAP services on the first LDAP server, everything works fine : 
the samba server detects the failed ldap server and switch to the 
available LDAP server.
Clients can be authenticated, everything works fine.

But, if the first LDAP server is unavailable (does not respond to ping), 
the samba server does not swith to the second LDAP server :

[2007/04/20 09:36:46, 0] lib/smbldap.c:smbldap_search_suffix(1346)
  smbldap_search_suffix: Problem during the LDAP search:  (Time limit 
exceeded)
[2007/04/20 09:36:46, 2] auth/auth.c:check_ntlm_password(317)
  check_ntlm_password:  Authentication for user [adminocs] -> [adminocs] 
FAILED with error NT_STATUS_NO_SUCH_USER
[2007/04/20 09:36:46, 2] smbd/server.c:exit_server(614)
  Closing connections

We have tried using smaller and greater values of ldap timeout in smb.conf 
but it does not help. ( from 5 to 600)
We have tried using smaller and greater values in the /etc/ldap.conf for 
bind_timelimit and timelimit (30 by default, from 5 to 300), but it does 
not help.

Here is our smb.conf related to ldap :

        passdb backend = ldapsam:"ldap://itdsd1l1.altissemiconductor.com 
ldap://itdsd2l2.altissemiconductor.com"
        ldap passwd sync = Yes
        ldap admin dn = 
cn=samba,ou=DSA,ou=manuf,o=altissemiconductor.com,cn=mfg
        ldap suffix = ou=manuf,o=altissemiconductor.com,cn=mfg
        ldap group suffix = ou=Groups
        ldap user suffix = ou=Users
        ldap machine suffix = ou=Computers
        ldap timeout = 15
        ldap ssl = start_tls

Is there a way to change the bind timeout for samba server to switch to 
the available node before the "search time limit exceeded" ?
Do I miss something ?

Regards,