On Thu, 20 May 2010 15:42:23 -0600 "Keith ." <lukano@xxxxxxxxx> wrote: > Thanks for the quick reply Neil, > > I tried the suggested syntax, excluding the array-size in order to > have mdadm give me the value - but it did not. I also tried grabbing > the current array size from df, but I got an error about being unable > to change array size in the same operation. > > So just to confirm I'm understanding you correctly ; mdadm -G > /dev/md127 --raid-devices 5 --backup=/root/backup - should generate > an error that provides the array-size value? Yes. Actually, you do probably need to change the size first: mdadm --grow /dev/md127 --array-size=xxxxx then once you are sure you haven't lost you data, change the number of devices. It might help if you ran the commands with "-v" and reported all the messages generated, and any kernel log messages. And maybe cat /proc/mdstat just to give us some more context.. Maybe you have a write-intent-bitmap attached to the array. You cannot reshape an array with one of those attached. NeilBron > > On Thu, May 20, 2010 at 3:34 PM, Neil Brown <neilb@xxxxxxx> wrote: > > On Thu, 20 May 2010 07:45:23 -0600 > > "Keith ." <lukano@xxxxxxxxx> wrote: > > > >> Does mdadm 3.1.x not support shrinking the number of disks in a RAID5 array? > >> > >> I have successfully converted my 6x1.5tb RAID6 array to a 6x1.5tb > >> RAID5 array. The issue that I now face is that one of those 6 drives > >> is failed / removed, and as a result - the new RAID5 array is down > >> it's parity drive. > >> > >> I knew I was short a disk when I started the process, but I was under > >> the assumption that mdadm now supported shrinking of RAID5/6 arrays. > >> Am I mistaken, or can anyone throw some suggestions at me so I can > >> give it a try? > > > > It should work. > > > > mdadm -G /dev/mdX --raid-devices 5 --array-size=XXXXX > > --backup=/root/backup-file > > > > If you don't give the 'array-size' value mdadm will tell you what it has to > > be. You need to be sure that all your data is already within that space. > > > > NeilBrown > > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
