perc 5/i returning global hot spare to hot spare after it took over for failed 0:0

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perc 5/i returning global hot spare to hot spare after it took over for failed 0:0

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I have a Dell 2950 with perc5i controller.  Four SAS drives.  Three in Raid 5 configuration with fourth drive as global hot spare.

Drive 0:0:0 failed and hot spare joined to array.  I have purchased a replacement drive and swapped in the first bay for the failed drive 0:0:0

So again the array before the failure was drives 0:0:0 and 0:0:1 and 0:0:2 (and 0:0:3 being the Global hot spare.)

After the failure the array became 0:0:1 and 0:0:2 and 0:0:3.  I have plugged the replacement drive into 0:0:0.

Now I have no idea how to make that new drive become a part of the array again, and return drive 0:0:3 to be the global hot spare.

 

Verified Answer
  • Hello tcfrancis

    The operation you described is normal. Once a hot spare takes the place of a failed drive it is no longer flagged as a hot spare. It becomes a permanent member of the array.

    There is a feature available in our PERC 6, 7, and 8 controllers called copyback. With copyback enabled the hot spare retains it's hot spare status even after becoming a member disk. Once the failed drive is replaced the hot spare will do a straight copy to the replacement rather than a rebuild. The straight copy is much faster than a rebuild because it does not need to calculate the array data.

    Since the PERC 5 does not have this feature the hot spare becomes a permanent member disk and the replacement drive will just sit in a ready state until you assign it to do something. If you want the replacement drive in slot 0 to become a member disk you will need to assign it as a hot spare. Then you will need to offline the drive you want to be the hot spare(0:0:3). This will rebuild PD 0 back into the array. You can then clear the configuration on PD 3. After you clear the config on PD 3 it should go to a ready state. Once it is in a ready state you can assign it as a hot spare again.

    Thanks

    Daniel Mysinger

    Download the Dell Quick Resource Locator app today to access PowerEdge support content on your mobile device! (iOS, Android, Windows)

All Replies
  • Hello tcfrancis

    The operation you described is normal. Once a hot spare takes the place of a failed drive it is no longer flagged as a hot spare. It becomes a permanent member of the array.

    There is a feature available in our PERC 6, 7, and 8 controllers called copyback. With copyback enabled the hot spare retains it's hot spare status even after becoming a member disk. Once the failed drive is replaced the hot spare will do a straight copy to the replacement rather than a rebuild. The straight copy is much faster than a rebuild because it does not need to calculate the array data.

    Since the PERC 5 does not have this feature the hot spare becomes a permanent member disk and the replacement drive will just sit in a ready state until you assign it to do something. If you want the replacement drive in slot 0 to become a member disk you will need to assign it as a hot spare. Then you will need to offline the drive you want to be the hot spare(0:0:3). This will rebuild PD 0 back into the array. You can then clear the configuration on PD 3. After you clear the config on PD 3 it should go to a ready state. Once it is in a ready state you can assign it as a hot spare again.

    Thanks

    Daniel Mysinger

    Download the Dell Quick Resource Locator app today to access PowerEdge support content on your mobile device! (iOS, Android, Windows)