I'm looking for a way to determine if CBT is being used or not in my image level backups. It appears that it is not as the backups are taking the same amount of time each time. However, everything is setup correctly, so does anyone know any troubleshooting methods or how I can verify if change block tracking is being used ?
CBT is change block tracking which is a feature of VMware. Avamar uses CBT for image level backups. I hope that answers your question.
* There is a known issue in the default configuration of the VMware Image Dataset for Avamar 5.0.0-407, 5.0.0-409 and 5.0.0-410 that prevents Avamar from using VMware Change Block Tracking to perform incremental backups of VMware virtual disks
* The utilize_change_block_list option is not set by default in this dataset, forcing full backups each time
There are two settings that affect the use of change block tracking. Please follow the instructions below to verify change block tracking is correctly enabled for each client (Item 1 below) and for the VMware Image Backup Dataset (Item 2).
This issue was corrected in Avamar Server version 5.0.1-32.
Please Note: After enabling change block tracking, one additional full backup will be run to generate a change block list. Subsequent backups should run as incremental backups.
Thanks Rudy, I had checked that previously, but I found out that it is an issue of having VM snapshots older than when CBT was enabled in VMware. Avamar ignores the CBT if it detects that previous snapshots are available. We resolved it by deleting all snapshots in vmware that were previous to CBT being enabled. Thanks everyone for the help. There is more information available here: http://vmguy.com/wordpress/index.php/archives/1538