On Fri, 25 Mar 2011 03:13:41 +0000 (UTC) shamim <shamim_99@xxxxxxxxx> wrote: > Hello Experts, > > Please help me to grow MULTIPATH RAID. > My problem: > I've Linux box which have MULTIPATH RAID created on them. Now we need to remove > those old LUN and move data onto new LUN presented to those boxes. > > My initially thought was to grow the current MULTIPATH RAID (/dev/md0) and > make old LUN as spare and then failed and then remove(Is this a right > approach?). When Iâm try adding new LUNs to it, they are getting added as spare > ( as shown below). And when I try to grow , it refuse to do so. Below are the > steps that I performed and error message.(Cannot reshaped!!) > ( I read somehwere that we canât grow MULTIPATH RAID, if it is TRUE, then what > would be suggested solution to move data from old LUNs to new LUNs) > Please help No, you cannot grow an md/multipath device. However you can simply create a new multipath config across the set of paths that you want to use. mdadm --stop /dev/md0 mdadm --create /dev/md0 --l multipath -n 4 ..list..of..paths... However I recommend that you stop using md/multipath and look in to using dm-multipath instead. See the 'multipath' command. dm-multipath is actively developed. md/multipath is not. NeilBrown > -------------------------------------------------- > > # mdadm --detail /dev/md0 > /dev/md0: > Version : 0.90 > Creation Time : Thu Mar 24 13:54:41 2011 > Raid Level : multipath > Array Size : 10486016 (10.00 GiB 10.74 GB) > Raid Devices : 2 > Total Devices : 4 > Preferred Minor : 0 > Persistence : Superblock is persistent > > Update Time : Thu Mar 24 13:54:41 2011 > State : clean > Active Devices : 2 > Working Devices : 4 > Failed Devices : 0 > Spare Devices : 2 > > UUID : xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx > Events : 0.3 > > Number Major Minor RaidDevice State > 0 65 0 0 active sync /dev/sdq > 1 8 96 1 active sync /dev/sdg > -------------------------------------------------------------------- > # mdadm /dev/md0 --add /dev/sdr /dev/sdh > mdadm: added /dev/sdr > mdadm: re-added /dev/sdh > > -------------------------------------------------------------------- > # mdadm --detail /dev/md0 > /dev/md0: > Version : 0.90 > Creation Time : Thu Mar 24 13:54:41 2011 > Raid Level : multipath > Array Size : 10486016 (10.00 GiB 10.74 GB) > Raid Devices : 2 > Total Devices : 4 > Preferred Minor : 0 > Persistence : Superblock is persistent > > Update Time : Thu Mar 24 13:54:41 2011 > State : clean > Active Devices : 2 > Working Devices : 4 > Failed Devices : 0 > Spare Devices : 2 > > UUID : xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx > Events : 0.3 > > Number Major Minor RaidDevice State > 0 65 0 0 active sync /dev/sdq > 1 8 96 1 active sync /dev/sdg > > 2 65 16 - spare /dev/sdr > 3 8 112 - spare /dev/sdh > > -------------------------------------------------------------------- > # mdadm --grow /dev/md0 --raid-disks=4 > mdadm: multipath array /dev/md0 cannot be reshaped. > > > > -- > 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 -- 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
