To hit the bad blocks, Controller task "Patrol Read" will also help. I hope here the root partition will also remain unaffected.
Regards -Vaibhav -----Original Message----- From: John Leach [mailto:j...@brightbox.co.uk] Sent: Monday, December 13, 2010 8:09 PM To: Kumar, Vaibhav Cc: linux-poweredge-Lists Subject: RE: H700 punctured stripe / emulated bad blocks On Mon, 2010-12-13 at 19:15 +0530, vaibhav_ku...@dell.com wrote: > Example syntax of omconfig tool to clear bad blocks. > > - to clear bad blocks on virtual disk 4 on controller 1, type: > > omconfig storage vdisk action=clearvdbadblocks > controller=1 vdisk=4 > > If it is returning "operation disabled", just check with latest OM available > on support site. > If OM is latest, check out the VD properties using omreport tool to confirm > that bad blocks is actually getting detected on VD or not. Hi Vaibhav, Thanks for the suggestion. I had used the command just like that, but got operation disabled: $ omconfig storage vdisk action=clearvdbadblocks controller=0 vdisk=0 Operation disabled. Read, action=clearvdbadblocks .Refer to the documentation for more information. omreport says there are no virtual disk bad blocks: $ omreport storage vdisk vdisk=0 controller=0 | grep Bad Virtual Disk Bad Blocks : No it's possible that the bad blocks aren't considered known until the background initialisation or the rebuild hits it, but at that point I lose my root partition and can't run omconfig. I'll try get a recovery os booted from a usb key with the dell tools. Any idea what the megacli command would be to clear the blocks? (megacli is much easier to install). Thanks, John. > -----Original Message----- > From: linux-poweredge-bounces-Lists On Behalf Of John Leach > Sent: Monday, December 13, 2010 7:00 PM > To: linux-poweredge-Lists > Subject: H700 punctured stripe / emulated bad blocks > > Hi, > > Our PERC H700 is remembering bad blocks on disks, even though they don't > exist. > > We had a mirror pair in a RAID10 get kicked out suddenly. A disk scan > showed the exact same block on both disks was bad. A suspicious start :) > > Dell support told us this was a "punctured raid stripe" and replacing > the disks, and recreating the raid container with a full initialisation > will fix it. They said the bad block had been "copied". > > Not content with wiping the entire container for the sake of one 256k > stripe, I've been investigating this for a few days now (the data on it > is not important - I'm interested in working this out for next time). > > I've tried a lot of arrangements, even copying one of the disks (with no > media errors encountered I might add) to a new disk, raid metadata and > all, and then trying to rebuild to a new disk from it - the rebuild > fails at the same point, offlining both disks. Note: *neither* of the > original disks are in the the array here. > > It boots fine and the virtual disk is available normally until the > background initialisation (or a rebuild) hits the supposed bad block and > then the vdisk is offlined. > > I've come to the conclusion that the RAID controller is emulating the > bad blocks. It's either remembering them in it's nvram, or they're > stored in the disk's raid metadata (though definitely not in the disks > GLIST, as I've checked that). > > It seems to only "discover" them when a background init or rebuild runs > though. But it's definitely finding them on disks that definitely do not > have them. > > Any thoughts? It is extremely frustrating that the only way to get the > controller to forget about these bad blocks seems to be a full wipe of > all the disks. > > Some possible hints: > > megacli tells me that "Disable Puncturing" is set to no. Maybe setting > this to yes would help (just for the rebuild to complete). Can't see how > to set this. > > the omconfig tool has a "clearvdbadblocks" action, which sounds > promising. It unfortunately returns "operation disabled" when executed. > I can't find any documentation about what this action does. > > Thanks, > > John. > -- > Brightbox > http://beta.brightbox.com/beta > > _______________________________________________ > Linux-PowerEdge mailing list > Linux-PowerEdge@dell.com > https://lists.us.dell.com/mailman/listinfo/linux-poweredge > Please read the FAQ at http://lists.us.dell.com/faq _______________________________________________ Linux-PowerEdge mailing list Linux-PowerEdge@dell.com https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
