Dear Neil, thanks for the info about set meaning of set-A, the difference between Device-ID and RaidDevice. > > Number Major Minor RaidDevice State > > 0 8 16 0 active sync set-A /dev/sdb > > 1 8 160 1 active sync set-B /dev/sdk > > 2 8 32 2 active sync set-A /dev/sdc > > 3 8 176 3 active sync set-B /dev/sdl > > 4 8 48 4 active sync set-A /dev/sdd > > 5 8 192 5 active sync set-B /dev/sdm > > 6 8 64 6 active sync set-A /dev/sde > > 7 8 208 7 active sync set-B /dev/sdn > > 8 8 80 8 active sync set-A /dev/sdf > > 9 8 224 9 active sync set-B /dev/sdo > > 10 8 96 10 active sync set-A /dev/sdg > > 11 8 240 11 active sync set-B /dev/sdp > > 12 8 112 12 active sync set-A /dev/sdh > > 14 8 128 13 active sync set-B /dev/sdi > > 13 65 0 14 active sync set-A /dev/sdq > > 15 65 16 15 active sync set-B /dev/sdr > > It's not "sync set-A", it is "active" and "sync" and "set-A". > When you have a RAID10 that can be seen as two sets of devices where one set > is mirrored to the other, they are labels as "set-A" and "set-B", just like > you assumed. The first time I noticed "set-A" and "set-B" in mdadm -D output was after the reshape operation started. If I understand you correct the real reason for these information to appear was not the reshape operation but growing the array from an odd number of drives (13) to an even number (16) > > What's the difference between column 1 and column 4 in > > mdadm -D output? > > column 1 identified the device. column 4 give the role that the device plays > in the array. > This seemed to make sense once, but it could be more confusing than helpful. What irritates me most is the fact that /proc/mdstat output lists the device id. For a raid10-array with near-2 layout and an even number of drives I was under the impression that the data is mirrored between all drives with even and all drives with odd numbers. In my case this is wrong: drives 0,2,4,6,8,10,12,13 are mirrored with drives 1,3,5,7,9,11,14,15. Spare-Drives are not shown with their number but with their role within the array (namely (S) ). So why not printing the role for all drives instead of their device-id. I would also suggest adding the set to mdstat-output, i.e: md5 : active raid10 sdb[A0] sdr[B7] sdq[A7] sdi[B6] sdh[A6] sdp[B5] sdg[A5] sdo[B4] sdf[A4] sdn[B3] sde[A3] sdm[B2] sdd[A2] sdl[B1] sdc[A1] sdk[B0] Is there any way to change the device-id? Kind regards Peter Koch -- 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
