Backup Exec Deduplication option is a great feature to reduce storage data and eliminate duplicate data to be backed up.

The Deduplication storage opotion provides media server side deduplication and remote server side deduplication to reduce network bandwith and optimize storage device. Please note that client side dedulication is available only on remote servers and not on Backup Exec server (media server).
Let’s check below how to create Deduplication backup job.
Go to Backup and Storage tab > right click on a remote server > choose Backup > choose Backup to deduplication disk storage

Now you can select the files and folders for backup selection by clicking Edit in left panel. It is advisable to run a complete full backup of any server to dedup storage first time for best dedup results. Now click Edit right panel

Now go to storage option and selection Dedup storage. By default Client side dedup is enabled for both Full and Incremental backup job.

Note: sometimes client side dedup backup may fail due to some network related issue then manually change to server side dedup and run the backup job.
Client side Dedup backup is failing
If client side dedup backups fail then you need to check if it fails for one server or multiple remote servers. Normally it fails or one specific server not all servers. It could be any server like windows, sql, oracle, exchange etc. Now in order to fix the client side dedup backup, first check how the server is added to Backup Exec server (media server) like, with IP address, or host name or fully qualified domain name.
If added with host name then add the remote server with IP address or vise-versa. You can go to backup and restore tab and locate the remote server which is failing client side dedup backup then right click on it and choose option Establish Trust. Then you can try the backup job. You also need to ensure that port 10000 is open on the remote server.
You can edit the backup job and go to Network and select IPV4 and try the backup job.
You can add IP and host name of the remote server to backup server’s host file, restart the server and then try the backup job. If reboot of the server is not possible then restart the backup exec services then try the backup job.
You can also install the latest patches on the Backup Exec and then update the remote agent on the affected remote server then reboot the server and try backup client side dedup backup, it should be successful. Dedup storage services can be restarted as well. However once the Backup Exec is patched up with latest, then all the remote servers should be updated as well.
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