Hi, I have a remote system with a raid1 of a data disk. I got a call from the person using the system that the application that writes to the data disk was not working. system drive is /dev/hda with separte partitions / , /var, /home, /tmp. data drive is linux software raid1 /dev/md0 with /dev/hdc1, /dev/hde1. I logged in remotely and discovered that the /var partition was full because many write errors from /dev/hde1 in /var/log/syslog. When I looked into cat /proc/mdstat i discovered that /dev/md0 was degraded because /dev/hdc1 had failed (there was an f there) and /dev/hde1 was carrying the load. I shut down the applications in background. I emptied out /var/log/syslog. I then removed /dev/hdc1 from the array /dev/md0. I had another pair of drives on the system that was part of another mirrored array /dev/md1 with no useful information stored on them. /dev/md1 /dev/hdf1 /dev/hdh1 I thought ok, let me detach /dev/hdf1 from the other array /dev/md1 and try attach it to /dev/md0 and rebuild the array /dev/md0. That way i would rescue the data on the threatening drive /dev/hde1 which is spewing out error messages to my /var/log/syslog and threatening to die! So stupidly (probably), I did mdadm /dev/md1 --fail /dev/hdf1 --remove /dev/hdf1 then i did mdadm /dev/md0 --add /dev/hdf1 Now when i did cat /proc/mdstat I see: md0 : active raid1 hdf1[2] hde1[0] 244195904 blocks [2/1] [U_] resync=DELAYED I don't see any rebuilding action going on. Did I have to do something like fdisk to the drive /dev/hdf1 before adding it to the array?? I didnt do anything to zero out the data that was on the disk (no data really just whatever was created on the disk when i made it part of an ext3 raid /dev/md1. I had fdisked it a while ago as a linux raid type partition... What do I do to rebuild the raid? Thanks millions for your help!! Mitchell - 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