When the Backup Exec services are restarted (The Advanced Device and Media Management service in particular), Backup Exec connects to the Remote Agent with Deduplication (RAD) to find the devices that are attached to the RAD. The RAD in turn connects to the Backup Exec Deduplication Manager service on the Media Server. Troubleshooting is based on finding out what step in the process is failing.
Step 1 - Run SGMon (SGMon.exe in the Backup Exec RAWS directory) on the RAD system. See http://www.symantec.com/docs/TECH136441
for details on the SGMon for Deduplication. Turn on logging for Job Engine, RAWS, Agent Browser, and enable debugging in the pd.conf file. Make sure to turn off debugging when you are done troubleshooting.
Step 2 - After starting SGMon on the remote system, restart the BE services on the media server (after verifying that there are no jobs in progress).
Step 3 - While the services are starting up on the media server, the SGMon on the remote server should start scrolling several pages or more of logging information. If there is no activity in the remote SGMon log throughout the time that the media server services are restarting, then the media server is having trouble connecting to port 10,000 on the remote agent. Check the name of the Remote Agent, verify that DNS is resolving the proper IP address, and try to telnet to port 10,000 on the remote agent from the media server. Also check that there are no firewall issues between the two servers.
Step 4 - If there is activity in the remote SGMon log, look through the log. It is most likely going to contain connection errors when it is trying to connect back to the deduplication services on the media server. Things to check for. Verify that the IP address that is being used is the right one (did DNS resolve the media server's IP address properly). Verify that telnet works from the remote server to the media server at ports 10082 and 10102. Verify that the Deduplication Folder still shows as being online at the media server by looking in the Backup Exec User Interface.
Step 5 - Verify that the remote agent has been installed properly with the right deduplication folder files. See http://www.symantec.com/docs/TECH150364
if this is an instllation of BE 2010 R2 for a potential issue with deduplication file installation on remote servers.
Step 6 - Verify that there are no firewalls blocking communication from the remote agent system to the media server.