Hi Ron, On 01/04/2014 08:28 AM, Ron Leach wrote: > List, good afternoon, > > I've recently needed to create a new raid1 array in an existing > (non-raid) Debian Wheezy system. The array has been created read-only, > and resync is PENDING; I didn't expect either of these conditions. > > Objective is to have an LVM built initially on mirrored unused 2TB > drives, with a view to growing the LVM with mirrored 3TB drives in the > future. The Logical volume will be exported over NFS, and will serve as > a repository for backups of other machines. The approach I am following > is, first, to create a raid1 array then, second, install an LVM over > that array, making sure that I create the LVM such that it can be expanded. > > (I think) I've created a raid1 on two empty and unpartitioned 2TB > drives, but am not seeing the results that the wiki > (https://raid.wiki.kernel.org/index.php/RAID_setup) seems to suggest. > > # cat /proc/mdstat > reports > > md0 : active (auto-read-only) raid1 sdc[1] sdb [0]' > 1953383360 blocks super 1.2 [2/2] [UU] > resync=PENDING > > This was the create command I used: > > # mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdb /dev/sdc > > I've read through man mdadm but had not expected 'auto-read-only', nor > 'resync=PENDING'. Has something gone wrong, for some reason? Or do I > need, simply, to set the array to be read-write? I wondered whether > 'create' does not 'start' the array, but it's reported as 'active', so I > think the array is started. I have not yet put a filesystem on the > array, because I am not sure the creation is ok. > > Grateful for any comment, and apologies for what must seem a very basic > question, "auto-read-only" is a safety measure that prevents any writes to an array until something in the data area is written. I don't remember the rules MD uses to determine if any given assemble/create operation qualifies, but it isn't an error. Just perform pvcreate on the array as you intended, and that'll switch the array to rw (and start the resync). HTH, Phil -- 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
