I was attempting to extend our main production NAS file pool on our NS-960 and ran into an issue. I had recently freed up 8 SATA disks from a block pool and was attempting to re-use them and extend a Celerra file pool. I created a new RAID Group and LUN that used the maximum capacity of the RAID Group. I then added the LUN to the celerra storage group, making sure to set the HLU to a number greater than 15. I then changed the setting on our main production file pool to auto-extend, and clicked on the “Rescan Storage Systems” option. Unfortunately rescanning produced an error every time it was run. I have done this exact same procedure in the past and it’s worked fine. Here is the error:
conflict:storageID-devID: disk=17 old:symm=APM00100600999,dev=001F new:symm=APM00100600999,dev=001F addr=c16t1l11
I checked the disks on the Celerra using the nas_disk –l command, and the new disk shows up as “in use” even though the rescan command didn’t properly complete.
[nasadmin@Celerra tools]$ nas_disk -l id inuse sizeMB storageID-devID type name servers 17 y 7513381 APM00100600999-001F CLATA d17 <BLANK>
Once the dvol is presented to Celerra (assuming the rescan goes fine) it should not be inuse until it is assigned to a storage pool and a file system uses it. In this case that didn’t happen. If you run /nas/tools/whereisfs (depending on your DART version, it may be “.whereisfs” with the dot) it shows a listing of every file system and which disk and which LUN they reside on. I verified that the disk was not in use using that command.
In order to be on the safe side, I opened an SR with EMC rather than simply deleting the disk. They suggested that the NAS database has a corruption. I’m going to have EMC’s Recovery Team check the usage of the diskvol and then delete it and re-add it. In order to engage the recovery team you need to sign a “Data Deletion Form” absolving EMC of any liability for data loss, which is standard practice when they delete volumes on a customer array. If there are any further caveats or important things to note after EMC has taken care of this I’ll update this post.