Hi andy,
Am 14.01.2024 um 09:15 schrieb Andy Smith:
On Sun, Jan 14, 2024 at 08:01:52AM +0000, Andy Smith wrote:
If necessary and if there is a way, I *can* nuke off the target
machine's "foo" volume group and recreate the RAID array if I have
to make it 512e format. But obviously I'd like some way to move this
disk image and have it still work without having to meddle inside it
much — it is a VM disk.
I think I may be able to use hdparm to reformat these Ultrastar DCs
from 4kn to 512e…
...
Thoughts?
Reshaping the target system's storage may be the quickest and most
reliable solution.
If you expect there may be future cases with similar problems -- the
other way around would be much worse, i.e. you have a source storage
with 4k sectors, and target that does not support it -- these posts
https://unix.stackexchange.com/questions/748208/lvm-and-device-mapper-logical-volume-device-sector-size
https://unix.stackexchange.com/questions/676534/creating-an-ssd-partition-with-a-different-block-size
might be good starting points to work out a real solution.
As far as I know, however, it is not possible to change the block sizes
using any of the software layers involved -- they all inherit from their
base layer, which means from the actual devices, eventually.
Fortunately, I never had to solve such issues myself, but that's
probably because I prefer working at the file system level. Block level
just has too many pitfalls for my simple tastes ;-)
I'm getting curious to see what happens if I have to mix 512- and
4k-sector disks in one RAID, though.
Cheers,
Arno
--
Arno Lehmann
IT-Service Lehmann
Sandstr. 6, 49080 Osnabrück
