I'm having a lot of trouble trying to backup a VM that has large, slow iSCSI disks. To begin with the VAW would immediately fail to backup any iSCSI disk with this error:
Error: The system cannot find the file specified. Failed to open I/O device Failed to open emulated disk. Failed to open disk for read. Failed to upload disk. Agent failed to process method {DataTransfer.SyncDisk}.
I found that the iSCSI LUNS on the SAN were not round numbers, so I rounded them up and this error stopped appearing. i.e. expanded 1.03452TB to 1.1TB
Now the agent is able to start backing up the iSCSI LUNs, last night it managed to backup 1TB of 1.6TB disk but fails with a new error:
No authority could be contacted for authentication
There were no issues with Active Directory at the time and there were other backup jobs that ran at the same time with no problems. Any idea whats wrong?
Also if I choose to Retry the job, it will delete the 538GB VBK file from the repository and will start the backup from zero. Is there a way to continue where it left off? The server being backed up is Windows 2012 R2 and has the CBT driver installed
Please, contact Veeam Support and share the logs with them so that they could investigate precise origins of both errors.
Also, highlight your Support Case ID here for the reference.
"No authority could be contacted for authentication" might point to authentication issues of Windows 2012 R2 server against a domain controller (Windows 2012 R2 server fell out of domain), which could have happened during backup.
Also if I choose to Retry the job, it will delete the 538GB VBK file from the repository and will start the backup from zero. Is there a way to continue where it left off?
Thanks for your reply. Support said the server briefly was unable to contact any domain controllers or perhaps lost all network connectivity briefly due to the load it was under. The solution was to create individual jobs and backup each volume one at a time
