Hi guys, i'm just reading this thread and sometimes i have some doubts about mdadm and mdmon too... others i know why it failed or something like... just some points, not related to the thread problem... in git there's some nice features talking with the user about use "git add <file>..." to include in what will be committed this kind of tips are very nice for beginner and new users, should be nice put some tips in mdadm too?! i don't remember the cases where tips should be used but maybe we could start a new mail thread to make this feature? thanks for the space guys, sorry can't help here in this thread 2013/9/13 Francis Moreau <francis.moro@xxxxxxxxx>: > Hi Neil, > > On Fri, Sep 13, 2013 at 10:43 PM, NeilBrown <neilb@xxxxxxx> wrote: >> On Fri, 13 Sep 2013 15:22:20 +0200 Francis Moreau <francis.moro@xxxxxxxxx> >> wrote: >> >>> Hi Neil, >>> >>> I'm probably doing something wrong since it's a pretty critical bug >>> but can't see what. >>> >>> I'm creating a RAID1 array with 1.2 metadata. After that I stop the >>> array, and restart the array with only one disk. I write random data >>> on the array and then stop it again: >>> >>> # mkfs.ext4 /dev/md125 >>> # mdadm --stop /dev/md125 >>> # mdadm -IRs /dev/loop0 >>> # mount /dev/md125 /mnt/ >>> # date >/mnt/foo >>> # umount /mnt >>> # mdadm --stop /dev/md125 >>> >>> Finally I restart the array with the 2 disks (one disk is outdated) >>> and mdadm happily activates the array without error. Note that I add >>> the outdated disk first in that case: >>> >>> # mdadm -IRs /dev/loop1 >>> mdadm: /dev/loop1 attached to /dev/md/array1, which has been started. >>> # mdadm -IRs /dev/loop0 >>> mdadm: /dev/loop0 attached to /dev/md/array1 which is already active. >> >> That's a worry. I'm not sure how to fix it. >> >> I would probably suggest you don't use "-IR" to add devices. That would make >> it a lot less likely to happen. >> > > Well I'm not sure how I should start an array... > > For example doing: > > # mdadm -I /dev/loop0 > # mdadm -I /dev/loop1 > # mdadm -R /dev/md125 > > works for array using metadata 1.2 but doesn't if the array is using > DDF (mdmon not started). To workaround this issue you suggested to use > -IRs: > > # mdadm -IRs /dev/loop0 > # mdadm -IRs /dev/loop1 > > but now mdadm can't detect outdated disk anymore. > > Could you suggest something to start an array which would work in all > cases (ddf or 1.2, add non-fresh disk...) ? > >> >>> # cat /proc/mdstat >>> Personalities : [raid1] >>> md125 : active raid1 loop0[0] loop1[1] >>> 117056 blocks super 1.2 [2/2] [UU] >>> # mount /dev/md125 /mnt >>> # ls /mnt/ >>> [ 457.321771] EXT4-fs error (device md125): ext4_lookup:1047: inode >>> #2: comm ls: deleted inode referenced: 12 >>> ls: cannot access /mnt/1: Input/output error >>> >>> If I add the outdated disk last I got this: >>> # mdadm -IRs /dev/loop0 >>> mdadm: /dev/loop0 attached to /dev/md/array1, which has been started. >>> # mdadm -IRs /dev/loop1 >>> mdadm: can only add /dev/loop1 to /dev/md/array1 as a spare, and >>> force-spare is not set. >>> mdadm: failed to add /dev/loop1 to existing array /dev/md/array1: >>> Invalid argument. >>> >>> which didn't tell me the reason why loop1 must be a spare. >> >> It must be a spare because it is out of date. >> > > Yes but I think mdadm should tell the reason, no ? > > Thanks > -- > Francis > -- > 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 -- 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
