[drbd-mc] LCMC display says "up to date" but DRBD is not

[Whit Blauvelt]

Hi,

I've got a fairly simple setup, that back some time ago was working well,
but at some point has slipped away from me. I have a number of KVM VMs which
have been set up by using a distinct LVM partition behind each, and then
using DRBD to mirror these between two servers via a dedicated crossover.
There are 6-8 VMs on each of the two servers, with both dedicated LVMs and
dedicated DRBD resources. I've been using current versions of LCMC along the
way to set up the DRBD mirroring. The LVMs have been set up using native
tools, and the KVM VMs through libvirt. 

To put the problem briefly, I've recently discovered, on shutting down VMs
on one server and then restarting the VMs on the other, after shifting DRBD
primary assignments, that the secondary DRBD storage has not kept up. This
is despite Connected/UpToDate claims in the Storage display of LCMC. 

Okay, how can this be? If it was failing like this and not showing
"UpToDate," that would make better sense. I'm assuming LCMC gets its data
directly from DRBD command line tools? So I won't see anything different
there? All the DRBD processes look to be running on the servers, for each of
the instances. Nonetheless this thing is failing, and in a bad way.

Whit