I'm currently building a Linux-HA cluster with a DRBD filesystem and wanted to check out how DRBD would work accross different distributions. To test DRDB I used an Ububtu and a Gentoo host and two loop devices of 256MB each (by default, DRBD uses 128MB for itself). Ubuntu Dapper has DRBD 0.7.15 on Kernel 2.6.15-25-386, while on Gentoo I got 0.7.18 with Kernel 2.6.15-gentoo-r1.