Host-based backup of Microsoft Hyper-V VMs.
Post Reply
asaraca
Novice
Posts: 4
Liked: never
Joined: Apr 06, 2010 2:53 pm
Contact:

Will Veeam Backup detect a corrupted file on dedup volume ?

Post by asaraca »

We encoutered an issue today on one of our virtualized file server on Hyper-V where we were unable to open a word document file that was on a dedup volume. When I went to try to restore that file on veeam, I had the same issue. The file wa succesfully restored, but I was unable to open it with Word. So is there a way with Veeam to be able to detect if a file is corrupted before backing it up to avoid to have a useless backup ?
Gostev
Chief Product Officer
Posts: 31814
Liked: 7302 times
Joined: Jan 01, 2006 1:01 am
Location: Baar, Switzerland
Contact:

Re: Will Veeam Backup detect a corrupted file on dedup volum

Post by Gostev »

No. Such corruption test would require opening each and every file with the respective application, and observing the result, which is obviously unrealistic thing to do (a single file server can easily have millions of files).

We do something very similar to such testing as a part of SureBackup functionality, but this one is normally used against core production applications, which have their data stored in just a handful of files (for example, Microsoft Exchange normally uses just a few mailbox database files).
asaraca
Novice
Posts: 4
Liked: never
Joined: Apr 06, 2010 2:53 pm
Contact:

Re: Will Veeam Backup detect a corrupted file on dedup volum

Post by asaraca »

But by doing some tests, I noticed that it's impossible to calculate a CRC on a file that is corrupt in a dedup volume. Would it not be enough to calculate the CRC of a file before backing it up to to catch most dedup errors/corruption before backing the file ?
foggy
Veeam Software
Posts: 21139
Liked: 2141 times
Joined: Jul 11, 2011 10:22 am
Full Name: Alexander Fogelson
Contact:

Re: Will Veeam Backup detect a corrupted file on dedup volum

Post by foggy »

Remember, Veeam B&R is an image-based backup solution, we do not do file-level processing.
Gostev
Chief Product Officer
Posts: 31814
Liked: 7302 times
Joined: Jan 01, 2006 1:01 am
Location: Baar, Switzerland
Contact:

Re: Will Veeam Backup detect a corrupted file on dedup volum

Post by Gostev »

Technically it is possible even with image-level processing, however this will result in huge processing overhead (backup window will go through the roof), and this sort of verification will not detect any file corruptions other than those caused by the storage itself, so it is mostly worthless anyway.
Post Reply

Who is online

Users browsing this forum: No registered users and 7 guests