[linux-lvm] [1019133-4yqc8ex4] LVM hangs after volume change

[Stuart D Gathman]

On Wed, 15 Apr 2020, Shock Media B.V. support wrote:

> We use an mdadm raid-config consisting of 4 or more SSD's/Disks where
> we use part of the disks for a raid1,raid10 or raid5. We create
> volumes on 2 nodes and use DRBD to keep these 2 volumes in sync and we
> run a virtual machine (using KVM) on this volume.

I've used DRBD for an almost identical setup, except only raid1 - we
were even cheaper that you. :->

I would first suspect DRBD hanging - and you should check the queue
stats to see if there is a backlog.  If you are using the paid version
with a userland smart buffering process, check whether that has died.