<snip>On Tue, Oct 19, 2010 at 07:34:19PM -0700, Nataraj wrote:fred smith wrote:helppain/backups/disks/
it appears that the devices are mounted - need to umount first??Well, I've already tried to use --fail and --remove on md125 and md126 but I'm told the members are still active. mdadm /dev/md126 --fail /dev/sdb1 --remove /dev/sdb1 mdadm /dev/md125 --fail /dev/sdb2 --remove /dev/sdb2 mdadm /dev/md126 --fail /dev/sdb1 --remove /dev/sdb1 mdadm: set /dev/sdb1 faulty in /dev/md126 mdadm: hot remove failed for /dev/sdb1: Device or resource busy with the intention of then re-adding them to md0 and md1. so I tried: mdadm /dev/md0 --fail /dev/sda1 --remove /dev/sda1 and got a similar message. at which point I knew I was in over my head.
When I create my Raid arrays, I always use the option --bitmap=internal. With this option set, a bitmap is used to keep track of which pages on the drive are out of date and then you only resync pages which need updating instead of recopying the whole drive when this happens. In the past I once added a bitmap to an existing raid1 array using something like this. This may not be the exact command, but I know it can be done: mdadm /dev/mdN --bitmap=internal Adding the bitmap is very worthwhile and saves time and risk of data loss by not having to recopy the whole partition. Nataraj _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos