Need assistance

Need assistance

[Gk Gk]

Hi All,


I have two nvme disks with different sector sizes of 512 and 4096
respectively. When I try
to use them in creating a volume group, it is complaining to set the
'allow_mixed_block_sizes' option in lvm.conf file. But I read elsewhere
that doing this would corrupt data.

Can anyone explain to me under what specific case/cases  will I loose data
if I allow mixed blocked sizes ?


Thanks
Kumar
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Need assistance

[David Teigland]

On Mon, Jan 30, 2023 at 06:07:03PM +0530, Gk Gk wrote:
> Hi All,
> 
> 
> I have two nvme disks with different sector sizes of 512 and 4096
> respectively. When I try
> to use them in creating a volume group, it is complaining to set the
> 'allow_mixed_block_sizes' option in lvm.conf file. But I read elsewhere
> that doing this would corrupt data.
> 
> Can anyone explain to me under what specific case/cases  will I loose data
> if I allow mixed blocked sizes ?

If an LV is using one disk, then there is clearly no problem.  If an LV is
using both disks, then we don't know all the issues that might appear --
linear/striped will be fine, but we've seen problems with cache,
writecache, snapshot.  Avoid pvmove or something where the disk under a
logical block might change.