[CentOS] drbd xen question

[Coert Waagmeester]

On Thu, 2009-08-20 at 09:38 -0600, Alan Sparks wrote:
> Ross Walker wrote:
> > On Aug 20, 2009, at 10:22 AM, Coert Waagmeester <lgroups at waagmeester.co.za 
> >  > wrote:
> >   
> >> Hello all,
> >>
> >>
> >> I am running drbd protocol A to a secondary machine to have  
> >> 'backups' of
> >> my xen domUs.
> >>
> >> Is it necessary to change the xen domains configs to use /dev/drbd*
> >> instead of the LVM volume that drbd mirrors, and which the xen domU  
> >> runs
> >> of?
> >>     
> >
> > Yes otherwise the data won't be replicated and your drbd volume will  
> > be inconsistent and need resync'd.
> >
> > -Ross
> >
> > _______________________________________________
> >   
> 
> To be clear, are you saying you have a DRBD partition on both host
> machines, and LVM on top of that to allocate LVs for host storage?
> 
> You would not want to bypass the LVM layer in that case.  The hosts
> would be still configured to map the LV devices into the domUs.  You
> need to go through the LVM layer, which uses the DRBD partition as a
> block physical device.  The writes down through the DRDB layer will
> still be replicated.
> -Alan
> 
Hello Alan,

This is my current setup:

Xen DomU
============
DRBD
============
LVM Volume
============
RAID 1


What I first wanted to do was:

DomU | DRBD
============
LVM Volume
============
RAID 1

Is this possible or not recommended?

Regards,
Coert