Hey, I installed 2 new data servers with a big (12TB) RAID6 mdraid. I formated the whole arrays with bad blocks checks. One server is moderately used (nfs on one md), while the other not. One week later, after the raid-check from cron, I get on both servers a few block_mismatch... 1976162368 on the used one and a tiny bit less on the other... That seems a tiny little bit high... I do the whole repair+recheck and it is back to zero. For brand new arrays, I am not very happy about the way mdraid seems to function (with the manual/croned checks, repairs, checks, checks, repairs, checks...) I will have to see next week how high the mismatches reach... Since my desktop is a RAID1 mdraid on 2 disks, I decided to have a look for fun... Apart from some low count mismatches, I did not have many problems... Did the whole check+repair+check on 3 mds and had a look at mdstat... md0 : active raid1 sdb1[1] sda1[0] 200704 blocks [2/2] [UU] md1 : active raid1 sdb2[1] 2048192 blocks [2/1] [_U] md2 : active raid1 sdb3[1] sda3[0] 2048192 blocks [2/2] [UU] md3 : active raid1 sdb6[1] sda6[0] 6144704 blocks [2/2] [UU] md4 : active raid1 sdb8[1] sda8[0] 2048192 blocks [2/2] [UU] md5 : active raid1 sda7[0] 4096448 blocks [2/1] [U_] md6 : active raid1 sdb5[2](F) sda5[0] 131074176 blocks [2/1] [U_] md7 : active raid1 sdb9[1] sda9[0] 340722432 blocks [2/2] [UU] It seems like I have some healthy volumes, some "failed partitions", and even some "missing partitions"... on both disks... And mdraid seems not alarmed about it... 1. Is there something to activate to get some kind of mdraid warnings? In /var/log/messages I cannot find any alarming message. 2. How to recover? Reboot? Or should I just mdadm --add the missing ones and --remove then --add the failed ones? Thx, JD