We run multiple tests daily to verify not only the integrity of the local images, but also the filesystems stored within.
Every day, we verify the integrity of not only the local images themselves, but also the file systems of the volumes that those images contain.
Chkdsk Verification - This occurs for each backed up volume's consolidated image that is created at the end the day. This helps us be certain that the data that you are backing up is in a readable state to begin with. If this is failing, there is typically some issues with the source volume.
MD5 Verification - This is ran for each new image and reoccurs weekly following that. We check the local images themselves against a stored hash to check against any bit-rot or other file degradation. If this is failing, depending on the image file that is running into issues, a rebase may be needed. Your dedicated engineer will let you know what we recommend for each situation.
Unless these sorts of test were being ran prior, you might slowly begin to notice more and more verification issues being reported. While having to run multiple chkdsk is burdensome, we encourage you to take notice to these failures if they continue to occur. Over the years, we have found that it is not uncommon for these additional verification process to be the harbingers of hardware failure and filesystem corruption. Because of this, while an offline chkdsk might fix some issues, it might not resolve the root cause.