This error happened after a power failure, where my hosts powered down without the guests being powered down first.<\/p>\n
Veeam was basically unable to freeze the VM’s to take a hot backup. The backup would complete however, but be extremely slow in the process. This is a result of Changed Block Tracking not telling Veeam what blocks have changed in an incremental (or full) backup.<\/p>\n
A lot of sites, including Veeam’s KB page, have suggested changing the CBT parameters in the offending VM’s, but this involves shutting down the guests.<\/p>\n
What worked for me was much less invasive.<\/p>\n
Edit the existing Veeam job, and click on Virtual Machines<\/strong><\/p>\n Click the Recalculate<\/strong> button to the right. I initially saw the calculated size was indeed zero, so it had no idea of the machine sizes it was backing up<\/p>\n Once the machines\/folders have recalculated and you have sizes populated, click Finish<\/strong>. This should then re-populate the Veeam database.<\/p>\n Hopefully you’ll have no more warnings, and also have a much faster backup timeframe.<\/p>\n","protected":false},"excerpt":{"rendered":" This error happened after a power failure, where my hosts powered down without the guests being powered down first. Veeam was basically unable to freeze the VM’s to take a hot backup. The backup would complete however, but be extremely slow in the process. This is a result of Changed… Continue reading