NetBackup has a feature called Enable file recovery from VM backup that allows the restore of individual files from VMware virtual machine backups. How is this any different than using GRT? Can you use GRT on a VM and restore a single file from a snapshot backup?
it is just a terminology "game". In less narrow sense, you can call this also "granular recovery", and some competivie systems call VM/file restores in this way.
But it has no relation to Enable granular recovery atribute in policy.
Because very general (non-NetBackup related) definition of granular recovery is that you can from higher level objects backups (VM here) restore also lower level objects (files here).
As mentioned, the concept of cataloguing, browsing, and restoring at a fine granularity is the same by any name. GRT is the Veritas trademark name when doing this for Exchange, SharePoint, and AD. For a VMware backup, it's internally known as "single file restore" (SFR). This name isn't externalized because of the conflict with Simplified File Restore (SFR) in OpsCenter.
With GRT for Exchange, SharePoint, or AD, there is a live browse that temporarily extends the catalog. You will see it triggered from a Q_IMAGE_LIST_FILES query to bpdbm. This is usually invoked because of an internal or external BPLIST request to bprd. Then bpdbm executes nblbc.exe on the client.
Another case is when a GRT-enabled Exchange backup is duplicated. This uses a Q_IMAGE_EXTEND_FILES_FILE query to bpdbm, which executes nblbc. (The proper name for the .f file is the files file.). As the query name implies, this duplication catalogs the mailbox items permanently.
For VMware backups, the catalog is extended under SLP control. You'll see a call from nbjm to bpbrm, and bpbrm executes nblbc.
In either case, nblbc does the live browse of the backup image. It's the live browse client (lbc).
I hope that this information will help you to look at the appropriate logs if you have to troubleshoot a problem.
An intersection: Exchange and SharePoint recovery from a VMware backup uses the VMware "single file recovery" feature, even for a database recovery. That's because the ASC part of the backup only catalogs; it doesn't send any data to your storage unit. During restore, the data is restored from the VMware backup image.