[Drbd-dev] 0.8 & GFS

[Joshua Mouch]

I'd like to test the newest version of 0.8 that is in SVN with GFS 6.1 with
the following storage failover setup:

_________        _________
|   A   |        |   B   |
|       |        |       |
| DiskA |<-DRBD->| DiskB |
---------        ---------

1) DiskA+DiskB should act as a networked stripped raid, which will be
accomplished by DRBD syncing the data between DiskA and DiskB.

2) Nodes A & B both provide an IMAP service (using Cyrus) with storage on
DiskA+DiskB.

3) GFS will ensure that locking occurs on DiskA+DiskB such that NodeA and
NodeB cannot write to the same spot on disk simultaneously.

However, I can't quite figure out how to accomplish part 3 so that I can
begin testing.  My first thought is export DiskA using GNBD and import it
into Node B and do the same for DiskB to node A so that Node A & B can "see"
both disks and therefore be able to perform locking.

_________        _________
|   A   |        |   B   |
|       |        |       |
| DiskA |<-DRBD->| DiskB |
|       |\      /|       |
|       | \    / |       |
| GnbdB |--\--/  |       |
|       |   \    |       |
|       |    \---| GnbdA |
---------        ---------

But that's where I get stuck.  Is this the correct approach?

Joshua Mouch