> Robin Hill <robin@xxxxxxxxxxxxxxx> hat am 6. März 2015 um 09:54 geschrieben: > > > On Thu Mar 05, 2015 at 06:56:00PM +0100, Stefan Lamby wrote: > > > Hello List. > > > > I was setting up a new machine using ubuntu 14.04.02 lts using its > > installer, > > configuring a raid 10 with 2 disks and lvm on top of it. I was using 2 disks > > and > > now I like to add 2 more disks to the array so i want to end up with 4 > > disks, no > > spare. > > > > Searching the internet I found that I am not able to --grow the array with > > the > > mdadm version this ubuntu is using (v3.2.5). > > Is that right? > > > > So I decided to build a new array that way and try to move my data > > afterwards, > > which failed: > > (Is it OK to do it that way or do you recommend another?) > > > > root@kvm15:~# mdadm --verbose --create --level=10 --raid-devices=4 /dev/md10 > > missing missing /dev/sdc1 /dev/sdd1 > > mdadm: layout defaults to n2 > > mdadm: layout defaults to n2 > > mdadm: chunk size defaults to 512K > > mdadm: /dev/sdc1 appears to be part of a raid array: > > level=raid10 devices=4 ctime=Fri Feb 27 15:49:14 2015 > > mdadm: /dev/sdd1 appears to be part of a raid array: > > level=raid10 devices=4 ctime=Fri Feb 27 15:49:14 2015 > > mdadm: size set to 1904165376K > > Continue creating array? y > > mdadm: Defaulting to version 1.2 metadata > > mdadm: RUN_ARRAY failed: Input/output error > > <<<<<<<<<<<<<<<<<<<<<<<<<<< > > root@kvm15:~# > > > IIRC, in a RAID10 setup, the redundant pair is held on adjacent drives. > You've specified two adjacent drives as missing, so the array cannot be > run. Try doing: > mdadm --verbose --create --level=10 --raid-devices=4 /dev/md10 \ > missing /dev/sdc1 missing /dev/sdd1 > Dang! One shot one catch, thank you so much! Dear Maintainer, please take a one-to-one copy of Robins explaination and print it if another dumb user like me tries to do the same and is caught also. This could help avoid a lot of frustration. There are posts in the internet which claim the order of the given devices is critical. Thank you all for taking the time to help. Stefan -- 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
