danb35
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- Joined
- Aug 16, 2011
- Messages
- 15,504
So my configuration's a little unusual, which sometimes leads me to wonder about odd things. My pool is composed of three mismatched RAIDZ2 vdevs: 6 x 6 TB, 6 x 4 TB, and 3 x 2 TB + 3 x 3 TB. Ordinarily you can't replace a drive with a smaller drive, but this setup leaves me with a few questions.
One of the 2 TB drives in the last vdev is failing, so I've ordered a 3 TB drive to replace it. If I also replace the other 2 TB drives with 3 TB drives, of course, the vdev (and thus the pool) will expand, but just replacing one drive won't have that effect. So after I replace one 2 TB drive with a 3 TB drive, 1 TB of the space on that 3 TB drive isn't going to be used in the vdev at all. Could I subsequently replace that 3 TB drive with another 2 TB drive? Logic suggests I could, but I've never had the opportunity to test.
Similarly, could I replace one of the existing 3 TB drives with a 2 TB drive? Again, logic suggests I should be able to--1 TB of the capacity on those drives isn't being used, since they're in a RAIDZ2 vdev with 2 TB drives.
I'm not likely to actually want to do this, but it does make me wonder.
One of the 2 TB drives in the last vdev is failing, so I've ordered a 3 TB drive to replace it. If I also replace the other 2 TB drives with 3 TB drives, of course, the vdev (and thus the pool) will expand, but just replacing one drive won't have that effect. So after I replace one 2 TB drive with a 3 TB drive, 1 TB of the space on that 3 TB drive isn't going to be used in the vdev at all. Could I subsequently replace that 3 TB drive with another 2 TB drive? Logic suggests I could, but I've never had the opportunity to test.
Similarly, could I replace one of the existing 3 TB drives with a 2 TB drive? Again, logic suggests I should be able to--1 TB of the capacity on those drives isn't being used, since they're in a RAIDZ2 vdev with 2 TB drives.
I'm not likely to actually want to do this, but it does make me wonder.