[CentOS] LDAP Server Access Problem

Mon Feb 22 05:48:09 UTC 2010
Paul R. Ganci <ganci at nurdog.com>

Hi All,

I am at my wits end. I have a LDAP server setup on a machine (the names
are changed to protect the innocent) example.mydomain.com running CentOS
5.4 and LDAP version 2.3.43-3. If I issue a ldapsearch command while
logged onto the LDAP server host I get a valid response back. For
example:

> ldapsearch -x -LLL -H ldaps://example.mydomain.com:636 "(uid=joker)" \
> sn uid
dn: uid=joker,ou=People,dc=mydomain,dc=com
uid: joker
sn: Nicholson

Everything works as expected. However if I try the same command from a
remote machine remote.mydomain.com the command just hangs. I can not
find a log entry anywhere that indicates something is wrong. I have
checked the obvious things I can check. For example I know that port 636
is open: 

> /etc/rc.d/init.d/iptables status | grep 636
110  ACCEPT     tcp  --  0.0.0.0/0            208.139.195.124     state
NEW,ESTABLISHED tcp dpt:636 
111  ACCEPT     udp  --  0.0.0.0/0            208.139.195.124     state
NEW,ESTABLISHED udp dpt:636

I have enabled access via /etc/hosts.allow:
> cat /etc/hosts.allow | grep slapd
slapd: ALL

I can see the server running and listening on port 636:
> netstat -l | grep ldaps
tcp        0      0 *:ldaps       *:*       LISTEN      
tcp        0      0 *:ldaps       *:*       LISTEN

> ps auxww | grep slapd
ldap     21865  0.0  0.2 467976  5860 ?        Ssl  19:54
0:02 /usr/sbin/slapd -h ldap:/// ldaps:/// -u ldap

I am missing something very obvious. Can anyone offer any clues? Thanks.

-- 
Paul (ganci at nurdog.com)