I have a storage pool that contains 7 physical disks and has two virtual disks created off it. One is a Tiered Mirror disk (containing two SSD's and two HDD's) that I use for VM storage. The other is a thinly provisioned parity disk (containing three HDDs) that I use for general file archiving.
The pool had a physical disk fail, which has happened before and has been no big deal - normally a virtual disk will be marked as degraded and will repair when the new disk arrives to replace the failed one. The virtual disk has always been usable while in the degraded condition. In this case though, the parity disk has been taken offline. When I try to re-attach it in Server Manager it gives an error saying "Error attaching or detaching virtual disk: failed to attach virtual disk to<server>. Failed."
While I haven't yet received the replacement disk for the failed one, I would have thought that this shouldn't matter and one disk failure in a parity disk would not take it offline? The fact that it did has me concerned that the whole virtual disk has failed from this one disk failure. What would have caused this to happen?