Legacy HDS Forums

VMWare ESX probing for new LUNs

Discussion created by Legacy HDS Forums on Apr 25, 2013
Latest reply on Nov 8, 2016 by cloud hunter

Originally posted by: lyle

I'm not the SAN admin, so may need to get more information for you on this one.  But...

We have a HDS AMS2100 with Brocade switches, and an older 9500V with Cisco switches.  Our vSphere ESX 4.1 servers use fiber HBAs to attach to these SANs.

One of the features of ESX is being able to select an HBA and tell ESX to "rescan" or probe it for newly attached LUNs.   That method works fine when adding new LUNs to an HBA that already has some.  But the rescan fails to recognize LUNs when they are the first ones to ever be seen by the HBA.  A reboot of ESX is required, and then the LUNs show up fine.

I've asked the VMWare forums why.   Multiple forum members there are all pointing to a SAN configuration issue.
One contributor, who has "guru" status and is the forum moderator, says:  "as long as the HBA is supported by VMware and the LUN zoned and presented correctly to the ESXi host all you will need to do is rescan and the LUN should be discovered"

Any ideas?   Thanks....Lyle