Dne 14. 09. 20 v 23:44 Gionatan Danti napsal(a):
Hi all,
I am testing lvmcache with VDO and I have issue with devices block size.
The big & slow VDO device is on top of a 4-disk MD RAID 10 device (itself on
top of dm-integrity). Over the VDO device I created a thinpool and a thinvol
[1]. When adding the cache device to the volume group via vgextend, I get an
error stating "Devices have inconsistent logical block sizes (4096 and 512)." [2]
Now, I know why the error shows and what i means. However, I don't know how to
force the cache device to act as a 4k sector device, and/if this is really
required to cache a VDO device.
My current workaround is to set VDO with --emulate512=enabled, but this can be
suboptimal and it is not recommended.
Any idea on what I am doing wrong?
Hi
LVM currently does not support mixing devices of different sector sizes within
a single VG as it brings lot of troubles we have not yet clear vision what
to do with all of them.
Also this combination of provisioned devices is not advised - since you are
combining 2 kind of devices on top of each other and it can be a big problem
to solve recovery case.
On lvm2 side we do not allow to use 'VDO LV' as backend for thin-pool device.
So ATM it's on a user to solve all the possible scenarios that may appear on
such device stack.
Zdenek
_______________________________________________
linux-lvm mailing list
linux-lvm@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
