Some news.

I move the Windows domU to a test cluster with the same software level.
But instead DRBD I have a shared SAN.
The migration works!
So the problem could be between DRBD and cLVM.

I append my DRBD configuration.

The software stack:
- the DRBD resource r0 is the PV for the clustered VG and
- the LVs are the Xen Images.

-------------------------------------------------
resource r0 {
startup {
become-primary-on both;
}
net {
allow-two-primaries;
after-sb-0pri discard-zero-changes;
after-sb-1pri discard-secondary;
after-sb-2pri disconnect;
verify-alg md5;
max-buffers 8192;
max-epoch-size 8192;
sndbuf-size 512k;
ko-count 4;
}
device /dev/drbd_r0 minor 0;
meta-disk internal;
on ha1infra {
address 172.17.232.11:7788;
disk /dev/disk/by-id/dm-uuid-part1-mpath-360080e50001c150e00000bee52eb1a88;
}
on ha2infra {
address 172.17.232.12:7788;
disk /dev/disk/by-id/scsi-360080e500036de180000035151d0f3e5-part1;
}
syncer {
rate 50M;
}
}


my problem appeared two weeks ago, around the time when
these two lvm updates came:

lvm2-2.02.98-0.29.1
lvm2-clvm-2.02.98-0.29.1

karl