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VMware SAN Backups errors

Level 5


Please help with this query, we are configuring VMware backups over SAN, we have several Datastores presented to the Media Server/Backup Host, but for some reason some VM backups are being performed over LAN (NBD), the Activity Monitor log indicates that they are not was able to access the disk via SAN Transport.

Performing validations, the WWID of the DataStore is not shown for any of the 6 paths that the storage has.

Another behavior is that when restarting the backup host, the paths are updated and several WWIDs / paths that were previously active are now no longer active.

Could it be some type of parameterization or limit on the number of devices that the backup host can handle?


Level 6

Hi @rafanto 

You don't mention the OS of the backup host. Even so if the OS is recent both Windows and Linux should be able to see many 1000's of LUNs without issue. 

The usual problem I've seen is incorrect SAN zoning to the datastore LUNs. I'd review this side first. Then if the HBA adaptors have software tools installed, use those to scan the HBA for what it can see. 



It's Linux (Flex appliance container instance), I don't know if under Flex Appliance architecture exists any issue or tunning to do.

Under the backup host we can see the disks and partitions (/dev/sda**) with the command lsblk for example, but with other command to view the WWID, this data don't show, for example:

/lib/udev/scsi_id --whitelisted --replace-whitespace --device=/dev/sdc

It coincides that on disks in which the WWID cannot be seen, SAN backups do not work.

At the Flex Appliance level, the WWID of the LUN is correct, the LUN is observed through all the paths that the Storage has (there are six), but at the media level they cannot be seen.


Hi @rafanto 
As it is a Flex instance there are steps to follow (which you may have done of course). 

From the Flex console, you need to assign the SAN ports to the instance and use them for VMware backups. After this is done, then the WWIDs should be visible to the instance. 

The steps to assign the ports can be found in the Admin guide for the Flex. 



In fact, these activities have been carried out, at the level of the Flex Appliance, if the same WWID of the LUN is observed for all the paths zoned against the storage (1 port of the flex appliance against 4 ports of the storage and another port of the flex appliance against 2 storage ports, total 6 paths), but we see the problem at the Media Server/Backup Host level, which at the OS level the WWID is not observed. The ports are assigned to the instance.

We have an open case with support to validate this issue.

I don't know if the configuration of the zones is correct and I should only make one zone with a Flex Appliance port and a Storage port (not against 4 or against 2)