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 -------------------------------------------------- # 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