hum, what diference about dmraid and mdraid? dm and md what's the diference? (md= multiple devices?! dm=? ) 2011/3/25 NeilBrown <neilb@xxxxxxx>: > 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 I’m 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 can’t 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 > -- Roberto Spadim Spadim Technology / SPAEmpresarial -- 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
