Video Screencast Help

Verify media set after duplication

Created: 21 May 2013 • Updated: 03 Jun 2013 | 4 comments
Marco Tafur's picture
This issue has been solved. See solution.


I have this customer who backups to disk only. Their jobs are backing up the resources first to a local SATA hard disks, then duplicate to external USB3 disks. So far, everythings working as it should.

However, duplication takes a lot of time, mostly by the verification process after the duplication job. Is it necessary to run a verify after duplication if the both the sources and destination are disk-based?



Operating Systems:

Comments 4 CommentsJump to latest comment

lmosla's picture

Hi, yes its reccommended to run verify even after disk based jobs.    The verify portion of the job can be scheduled to run seperately but it needs to be ran at least periodically. 

Please see my short blog on it


Marco Tafur's picture

Interesting article.

However, to clarify, the verify process is just for checking if the written data on the duplicated media is consistent or legible logically.

My question about the verification process in duplication jobs arised because of these ideas:

- Media sets are already verified when created during the initial backup jobs (taking about 50% of the total backup time, hence the backup window shortens a lot). Right now backup window is 12 hours, with 1.1TB of data to be written, starting as 19:00 and finishing at 0700 the next day.

- Duplication media is not tape. They are brand new USB3 disks (Lacie d2 Quadra, recommeded btw). Duplication takes about 8 hours and starts at 9:00 hrs to 17:00pm same day. So, avoiding verify will halve the time needed to complete these jobs. 

However, another question arises: does the duplication media is a mere copy of existing media sets or a more complicated process? 

pkh's picture

Other than copying the backup set, the duplicate process also updates the catalog so that you can use the duplicated backup set.

The verify process for the duplicated backup set is to ensure that it can be read back.  If you skip the verify process, then there is no guarantee that the duplicated backup set is written correctly and can be read back.  The verification process for the source backup set has nothing to do with the verification of the duplicated backup set.

Marco Tafur's picture

Then verify:on will be the settings for jobs. If it is for the best, my customer will have to live with it...hehe.

Thanks for the reply!