On Wed, 17 Mar 2004, Neil Brown wrote: > On Wednesday March 17, Holger.Kiehl@dwd.de wrote: > > Hello > > > > I have a problem with setting up a raid10 array with mdadm. With raidtools > > it runs fine, but this might be because I have been using it for a very > > long time. > > > > The array consists of 6 SCSI disk /dev/sd[abcdef]1 and creating and > > starting the raid1 is no proplem. Creating the raid0 is also no problem > > but starting it after it is stopped does not work. > > > > Here my /etc/mdadm.conf: > > > > DEVICE /dev/hda[2356] /dev/hde[2356] > > DEVICE /dev/sd[abcdef]1 > > ARRAY /dev/md0 level=raid1 num-devices=2 UUID=758b2a4e:74f182df:282c9a7e:0246977b > > ARRAY /dev/md1 level=raid1 num-devices=2 UUID=728311df:5491265a:29de2fa5:a1042914 > > ARRAY /dev/md2 level=raid1 num-devices=2 UUID=37bd8c5a:9e7efc91:e7537d56:b56c8eef devices=/dev/hda6,/dev/hda5,/dev/hde6,/dev/hde5,/dev/sdd1,/dev/sda1 spare-group=group1 > > ARRAY /dev/md3 level=raid1 num-devices=2 UUID=01bc8c7b:c3eb887e:79eb423d:bd46305f devices=/dev/sde1,/dev/sdb1 spare-group=group1 > > ARRAY /dev/md4 level=raid1 num-devices=2 UUID=72fe4455:cc7965b5:4fe2f4d0:2a5523ce devices=/dev/sdf1,/dev/sdc1 spare-group=group1 > > ARRAY /dev/md5 level=raid0 num-devices=3 UUID=c1565e2b:12c85143:d2fcffa2:12791897 devices=/dev/md2,/dev/md3,/dev/md4 > > > > Doing a "mdadm -A /dev/md5" I get: > > > > mdadm: no devices found for /dev/md5 > > > > md5 should be the raid0 consisting of the three raid1's (md2, md3, md4). > > What am I doing wrong? > > You need > > DEVICE /dev/md? > > or similar in mdadm.conf > Correct, that was a very obvious error on my part! Thanks! > (and you probably don't want the devices= entries at all). > Hmm, I was thinking to leave the UUID part away because the SCSI disk are hotswap and I thought it would be much easier when you put in a new disk. With UUID will it not refuse the new disk/partition? Does it not require more steps when you replace a failed disk? Also I find the devices= entry usefull in that it tells me what disks are being used for the array. If for example the array is offline for whatever reason, I like to have one file where all information is stored so it can be recreated with a completely new set of disks. What is missing is the chunk-size entry. It looks as if I do not understand the concept of mdadm.conf :( Holger - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
