Pool A: 4x (new) 8TB drives, no duplication, no mounting.
Pool B: ~20x (old and used) 750GB - 2TB range drives, no duplication, no mounting. Pool A ~ Pool B in terms of space.
Pool C: Pool A & Pool B, 2x duplication, mounted to a drive letter and network shared.
(pending): 4x (new) 8TB drives, offsite, with a nightly sync with Pool C.
I want full duplication, and I want to make use of all the old drives I have, but I also don't particularly trust the old drives. As such, I want a copy of data to exist on both the new drives and the old drives. If I'd just gone with one pool, there'd be the likely probability that some data would be mirrored across just two of the old drives, which have a higher chance of mutual failure than an old drive and one of the newer drives.
In the last week, I've had one of the old drives show SMART errors (that aren't particularly alarming, not enough to remove the drive from the pool), and another drive has apparently reported unreadable sectors.
It's the latter I'd like to ask about. Scanner is reporting the drive as "Damaged", and DP naturally started moving data off of the drive onto other drives in Pool B (it's nearly done at this point). The drive reports as having 2.5KB of missing data due to 5 unreadable sectors, and that this data is likely permanently lost; since Pool B itself is not duplicated, Scanner rationally sees any data that gets lost from this pool as gone forever. However, this data is in fact mirrored on Pool A (via the duplication of Pool C).
My question is this: what will DP do now, in regards to Pool C? Will it scan Pool A and Pool B, see the discrepancy in mirroring, and copy over the missing data from Pool A to Pool B? Or will it sync Pool A to match Pool B, and remove the 2.5KB of data on Pool A as well?
Question
banderon
Howdy,
I have a question on how DP's duplication works.
My setup:
I want full duplication, and I want to make use of all the old drives I have, but I also don't particularly trust the old drives. As such, I want a copy of data to exist on both the new drives and the old drives. If I'd just gone with one pool, there'd be the likely probability that some data would be mirrored across just two of the old drives, which have a higher chance of mutual failure than an old drive and one of the newer drives.
In the last week, I've had one of the old drives show SMART errors (that aren't particularly alarming, not enough to remove the drive from the pool), and another drive has apparently reported unreadable sectors.
It's the latter I'd like to ask about. Scanner is reporting the drive as "Damaged", and DP naturally started moving data off of the drive onto other drives in Pool B (it's nearly done at this point). The drive reports as having 2.5KB of missing data due to 5 unreadable sectors, and that this data is likely permanently lost; since Pool B itself is not duplicated, Scanner rationally sees any data that gets lost from this pool as gone forever. However, this data is in fact mirrored on Pool A (via the duplication of Pool C).
My question is this: what will DP do now, in regards to Pool C? Will it scan Pool A and Pool B, see the discrepancy in mirroring, and copy over the missing data from Pool A to Pool B? Or will it sync Pool A to match Pool B, and remove the 2.5KB of data on Pool A as well?
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