In our testing, md raid10 is about 30% faster than megaraid's internal raid10.

Here are steps to replace hardware megaraid with software md5 on ganeti.




root@lib30:/srv/gnt-info# gnt-node migrate lib28

root@lib30:/srv/gnt-info# gnt-node modify --drained yes lib28

root@lib30:/srv/gnt-info# hbal -L -X



This will migrate instances from node, marked it as drained and then hbal will re-distribute drbd disks
from it to rest of cluster.

Alternative is to use modify -t plain, but that requires instance reboot.