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I have a RAID 5 array of 4 disks. In the last 2 days I began to see these messages in the log:

Jun 13 23:01:05 localhost smartd[4537]: Device: /dev/sda [SAT], 1 Currently unreadable (pending) sectors
Jun 13 23:01:05 localhost smartd[4537]: Device: /dev/sdb [SAT], 2 Currently unreadable (pending) sectors

If I have 2 faulty disks then the array should not show all disks OK:

md0 : active raid1 sdd1[3] sdb1[1] sdc1[2] sda1[0]
      64128 blocks [4/4] [UUUU]

Strangely there are no other problems just the log messages. I am worried because sda is new and I previously had problems with sdb. (Completely died but the guy who sold it to me fixed it somehow.) Am I in danger of losing data? What should I do now?

share|improve this question
sdb "completely died but was fixed somehow"? that doesn't sound like a drive i'd be using in any important capacity now. sounds like it's time to make sure you've got a complete, usable, tested backup somewhere safe. – quack quixote Jun 13 '10 at 23:01
I agree but unfortunately I have nowhere near enough capacity to do that. Only the most important stuff is backed up. I have warranty for all the drives so I could replace them one at a time. I am not sure they would replace working drives. I could wait for one to fail but they can fail simultaneously. I could buy new ones but as far as I know this can be a false alarm. (2 bad drives => data loss but no data is lost) – stribika Jun 14 '10 at 15:24

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