[Linux-cluster] cmirror status

[Jonathan Brassow]

On Tue, 2005-12-20 at 14:53 +0100, Sylvain Coutant wrote:
> Hi,
> 
> I wonder about the status (production ready ?) of cmirror and how it should be used.

cmirror won't be production ready until it gets some more testing.

> 
> >From the CVS, I see it is included in the STABLE and RHEL4 branches but TODO is over-aged and states not to use it for stable production.

RHEL4 is the only branch that really makes sense for cmirror right now,
and will require U3+ kernels.

> 
> Also I didn't found useful docs on how to make use of it ... The README could have a more lines to better explain how to interact with device mapper.

Yeah, sorry 'bout that.  New LVM packages are needed that support
mirroring.  LVM will "do the right thing" when it encounters volume
groups that are clustered vs non-clustered, and you should be able to
switch between the two w/o having to re-sync your volume.

If you'd like to use [cluster] mirroring before LVM is ready, I'll give
you the table arguments.  Note that LVM has a big part in how recovery
happens.

 brassow