So, any opinons on this bug from the people in here?
http://www.educationalcentre.co.uk/...kb2090639-causes-data-corruption-for-backups/
Veeam Community Forums Digest
THE WORD FROM GOSTEV
Unfortunately, I also have some not so good news to share. Earlier this month, VMware has quietly published a KB article about a rather terrible CBT bug that exists in all versions of ESX(i) since changed block tracking functionality was first introduced. We have been working directly with VMware to confirm the exact scope of the issue and update the KB article with more details. But the main point is that your backups and replicas for all VMs that had its virtual disk size expanded beyond 128 GB at some point may be unrecoverable. We are working on a hot fix for both 7.0 Patch 4 and 8.0 code branches that will reset CBT automatically upon detecting source virtual disk size change. Meanwhile, I recommend manual CBT reset for all VMs that had their virtual disks expanded at some point by disabling CBT (the following Veeam job run will re-enable CBT automatically). Perhaps, just disabling CBT on all VMs with a PowerCLI script might be the best idea - but keep in mind that the following job runs will take much longer, so best is to do this before the weekend.
These kind of issues always make me stress the importance of SureBackup. Many users consider setting up SureBackup jobs to be a low priority when compared to actual backups - however, only SureBackup is able to catch these kind of issues. Interestingly enough, a lot of people seem to recognize the importance of backup integrity testing, in fact our Backup Validator tool seems to be very popular. I do agree that integrity checks are important, in fact I have dedicated the entire VeeamON breakout session to "classic" data corruption issues. However, integrity checks will not detect corruption issues similar to the above. And yet, these sort of issues are much more common. I cannot stress this enough, especially in light of enhancements we are adding to our Backup Validator tool in v8. These enhancements are based on your feedback, but they do not mean that Backup Validator is the future. It has its use in detecting storage level corruptions, but only SureBackup can guarantee you the ability to recover.
http://www.educationalcentre.co.uk/...kb2090639-causes-data-corruption-for-backups/
Veeam Community Forums Digest
October 20 - October 26, 2014
THE WORD FROM GOSTEV
Unfortunately, I also have some not so good news to share. Earlier this month, VMware has quietly published a KB article about a rather terrible CBT bug that exists in all versions of ESX(i) since changed block tracking functionality was first introduced. We have been working directly with VMware to confirm the exact scope of the issue and update the KB article with more details. But the main point is that your backups and replicas for all VMs that had its virtual disk size expanded beyond 128 GB at some point may be unrecoverable. We are working on a hot fix for both 7.0 Patch 4 and 8.0 code branches that will reset CBT automatically upon detecting source virtual disk size change. Meanwhile, I recommend manual CBT reset for all VMs that had their virtual disks expanded at some point by disabling CBT (the following Veeam job run will re-enable CBT automatically). Perhaps, just disabling CBT on all VMs with a PowerCLI script might be the best idea - but keep in mind that the following job runs will take much longer, so best is to do this before the weekend.
These kind of issues always make me stress the importance of SureBackup. Many users consider setting up SureBackup jobs to be a low priority when compared to actual backups - however, only SureBackup is able to catch these kind of issues. Interestingly enough, a lot of people seem to recognize the importance of backup integrity testing, in fact our Backup Validator tool seems to be very popular. I do agree that integrity checks are important, in fact I have dedicated the entire VeeamON breakout session to "classic" data corruption issues. However, integrity checks will not detect corruption issues similar to the above. And yet, these sort of issues are much more common. I cannot stress this enough, especially in light of enhancements we are adding to our Backup Validator tool in v8. These enhancements are based on your feedback, but they do not mean that Backup Validator is the future. It has its use in detecting storage level corruptions, but only SureBackup can guarantee you the ability to recover.
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