I have been using avamar for SQL about 2 years. Initially we used the Avamar with the built in grid storage.

We didn't use the avamar scheduler to run SQL backups but used our enterprise scheduler to run batch scripts on each SQL client. Avamar has a Command Line interface in addition to the GUI. Our environment consists of SQL 2005 on Server 2003 to SQL 2012 on Server 2012 and everything in between.

For almost two years we experienced issues where the backup executables would hang and not complete. This required us to have to kill the processes and restart. This could happen couple times a week or a night.

Recently we migrated the storage off of the avamar grid to our Data domain storage. The ablility to do this was a recent addition to avamar software. After doing this the performance is much better and the hangs seem to have disappeared.

I only perform FULL backups using avamar. I use native scripts for the transaction log backups and back them up directly to our Data Domain.

Let me know if you have any other questions.

Thanks

Mark