Last time out, we went over the reasons why Avamar is different and faster than other backup applications for backing up unstructured data sets.
This time out, I thought we should turn our attention to NAS (filer) backup under Avamar. Again, we see big differences in how Avamar handles NDMP backups. Again, we see that Avamar backups can take only 10% of the time of a standard NDMP backup. But it turns out that the reasons for this are totally different than the reasons that Avamar is so fast at unstructured data backups.
First, a bit of background. Avamar doesn't really do full or incremental backups. Avamar does a backup. That backup data is written together with existing backup data on an Avamar server in a way that a full system image is present for every day on which a backup occurred.