Hi All,
The question is simple, if an historic array has been created with 0.90
metadata version, is it possible to upgrade that to 1.x, and if so, how?
https://serverfault.com/questions/142318/can-you-change-the-metadata-version-on-an-existing-array
Is the best reference I could find and boils down to "no" but it's not a
definitive.
The disks in the specific array (12 disks, RAID6) has been upgraded by
way of rebuild one by one from 4TB to 10TB, but with the 0.90 metadata
only ~4.4TB of each drive can be utilized.
I can *potentially* work around this by adding four of the 4TB drives
back, creating a new temporary array with the correct format, then using
pvmove to repeatedly clear data out of the upper end of the historic
raid, shrinking the array by a drive, adding same to the replacement
array. I just need to make sure I'm going to be able to get the last
bit of data migrated (sizing thing).
For obvious reasons an upgrade of the metadata will be simpler, if
possible. No sensible backup option here ... unless I can find around
80TB of storage for full system backup (there are currently three arrays
in the system, one other array will run into the same problem
eventually). But now that I'm aware of the problem we can re-emptively
make a plan to avoid the problem for that case.
Kind regards,
Jaco
