it's failing at the time of mapping.
these errors mostly come because of highly fragmented disk or Bad indexes.
try.
1. defrg of drive in question
2. run chkdsk on drive and fix errors.
- if above 2 doesn't work for you. look at your Application Event Logs at the time of this failure for Events for VxMS.
- Also look in to your System Event logs. your system might be busy and it failed to flush data.
also, it will be helpful if you can tell us
1. netbackup Client version?
2. Do you havea big exclude list?Big Exclude list increases the mapping time. you can read more on this below.
www-secure.symantec.com/connect/articles/what-so-special-about-directread-registry-entry-flashbackup
www-secure.symantec.com/connect/blogs/slow-mapping-flashbackup-look-your-exclude-file-list
hope it helps.
~ Pravs