problem connecting to LDAP server

[Wang, Holly]

Hello,

I can't connect to our LDAP server from Shibboleth. At the same time, I can use the same setting connect to it from another web application on another server. 

LDAP setting in attribute-resolver.xml: 
ldapURL="ldap://csunldapserver.csun.edu:389" baseDN="ou=***,ou=***,o=***" principal="cn=directory manager" principalCredential="password"

I can telnet this LDAP server from  Shibboleth server without any problem. I can connect to this LDAP server with same setting from another web application, and also from a LDAP client side software. 

The error I got in opt/shibboleth/logs:  


11:42:00.026 - DEBUG [edu.vt.middleware.ldap.handler.DefaultConnectionHandler:73] - Bind with the following parameters:
11:42:00.027 - DEBUG [edu.vt.middleware.ldap.handler.DefaultConnectionHandler:74] -   authtype = simple
11:42:00.027 - DEBUG [edu.vt.middleware.ldap.handler.DefaultConnectionHandler:75] -   dn = cn=directory manager
11:42:00.027 - DEBUG [edu.vt.middleware.ldap.handler.DefaultConnectionHandler:82] -   credential = <suppressed>
11:42:00.030 - DEBUG [edu.vt.middleware.ldap.handler.DefaultConnectionHandler:167] - Error connecting to LDAP URL: ldap:// csunldapserver.csun.edu:389
javax.naming.CommunicationException: simple bind failed: csunldapserver.csun.edu:389


Any advice? Thanks