Setting Up and Troubleshooting LDAPS Authentication in Forefront TMG 2010

re: Setting Up and Troubleshooting LDAPS Authentication in Forefront TMG 2010

yargray — Wed, 01 May 2013 08:27:25 GMT

Unfortunately I am having similar problems as described above. We get the " LDAP server not responding" alert quite regularly, but in our case all functionality appears to be fine and the LDP test described in this blog is fine too.

Any suggestions on finding the root cause for this would be much appreciated! Alternatively, if this is some kind of "false" alert, is it safe to override it in SCOM?

Many thanks,

re: Setting Up and Troubleshooting LDAPS Authentication in Forefront TMG 2010

Karsten Hedemann — Fri, 15 Mar 2013 13:59:53 GMT

As jr_suisse I'm experiencing exactly the same issue. I have found nothing wrong in the network and TMG is configured correctly. It's the same on two different domains.

I have been looking at timeout settings etc., but haven't had luck to figure out what was wrong.

And as the warnings comes in the Application Event Log, the user (if logged in) experience a timeout until the Event Log 'Description: The connection to the LDAP server x.domain.local was restored' is logged.

If a user is about to logon, they can also experience long login times and the same Event Log is logged, and Again when 'Description: The connection to the LDAP server x.domain.local was restored' is logged the session may even be signed in and the user can browse the SharePoint site, or the timeout was so long that the user need to login Again.

re: Setting Up and Troubleshooting LDAPS Authentication in Forefront TMG 2010

jr_suisse — Wed, 25 Apr 2012 07:54:37 GMT

Very good post. I've implemented it on my TMG NLB. Normally it works fine. But in the last time when i have checked the log i saw the following Alert Information:

"The LDAP server x.domain.local did not respond. If the server is physically reachable and a secure (SSL) connection is required, this event may be caused by failure of the SSL handshake.This event may also occur when the credentials used to connect to the LDAP server to verify the status and change the password of an account are rejected by the server "

After a few minutes i have the following Alert Information:

"Description: The connection to the LDAP server x.domain.local was restored."

I can't understand why it happens. I checked the FW between the TMG's and the DC. I checked the DC, everything semms to work. Also the Certificatas are ok. Wiht the LDP.exe Toll i can successful create a connection. Analysing the network trace with wireshark shows me, that there are no ssl handshake or tcp problems. Have you ever seen this? Do you have any ideas? I'm searching for a solutinos since weeks but I can't find anything. Thank you