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

[Rasto Levrinc]

On Wed, Oct 24, 2012 at 8:38 PM, Whit Blauvelt <whit.drbd at transpect.com> wrote:
> 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.

Hi,

The display in LCMC should be ok. Your problem is probably either your
config or an administration error at some point, forcing the DRBD to think
the data are up-to-date. You can run online verify to check if your
secondary has the same data as primary, before finding out the hard way. For
DRBD specific questions, you should ask in drbd-user mailing list.

Rasto

>
> 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



-- 
Dipl.-Ing. Rastislav Levrinc
rasto.levrinc at gmail.com
Linux Cluster Management Console
http://lcmc.sf.net/