Challenge
Backups of VMs from ESXi hosts with the enabled Content Based Read Cache (CBRC) fail and you get the following errors in HTML report generated for a failed job:Error Hot-add of digest enabled disk not supported scsi0:1. Error Failed to attach disk 2000 to source Linux backup proxy <IP address> (<GUID>) (System.Exception)
Cause
This issue occurs if Linux proxy is selected in a backup job, when Veeam tries to hot-add a virtual disk to a VM which is deployed on the ESXi host with the CBRC option enabled.Due to the VMware limitation, you cannot attach disks to VMs while they are powered-on.
Veeam Linux proxies have only one transport mode (hot-add) so far. That is not the case with regular Windows proxies.
According to VMware documentation CBRC feature was introduced in vSphere 5.1, thus may affect all systems with this version and above.
Solution
To back up a VM with the enbaled CBRC option, you can try the following options:- Power-off a VM that you want to back up. You can use the pre-job script to power off this VM.
- Create a new backup job for affected VMs and configure a Windows backup proxy with failover to the Network mode for this job.
- Turn off the CBRC option the in ESXi host settings. To learn how to turn off the CBRC option, see the VMware Horizon 7 Documentation, section Configure View Storage Accelerator for vCenter Server.