some tips:
* load module: modprobe drbd
* make a link first: ln -s /sbin/drbdadm /usr/sbin/drbdadm
* there is a warning about drbd-kmp when using Yast, just keep press Ok or Next
* use device name as /dev/drbd_XXX minor XXX (the _ must be presented)
* manually run drbdadm create-md <RES>
* manually run drbdadm up <RES>
* manually run drbdadm -- --overwrite-data-of-peer primay <RES> on 1st node, and drbdadm secondary <RES> on 2nd node
* check status by cat /proc/drbd, to make sure connected and Primary/Secondary on 1st node and Secondary/Primary on 2nd node
Some Errors:
* unknown minor
- run drbdadm up <RES>
* no resources defined!
- use Yast to create resource
* ds:Diskless/UpToDate in /proc/drbd
- drbdadm down <RES>; drbdadm up <RES>
* (104) Can not open backing device
- delect and re-create partition, ( may needs a reboot)
* staying cs:StandAlone in /proc/drbd on 2nd node
- drbdadm -- --discard-my-data connect <RES>
