Tips of creating HA Cluster on OpenSuse 13.2 / 42.1
* Make sure NTP, DNS and firewall are configured properly.
* Avoid to use LVM for ISCSI target device, use raw partition instead.
* It is recommended to use Disk ID(/dev/disk/by-id/xxxxxx) rather than path (/dev/sdaX).
* Initname (iqn) must be unique to all cluster nodes. It could be regenerated by iscsi-iname command.
* No auth for discovery, but login. Incoming should be enough.
* The softdog module must be loaded for SBD (fencing system) before cluster initialization, if no hardware solution is available.
* Run mkfs.ocfs2 with stack and cluster names before using Hawk ocfs2 wizard. (mkfs.ocfs2 --cluster-stack=pcmk --cluster-name=hacluser /dev/disk/by-id/XXXXXX ; mounted.ocfs2 -t)
* Sync configuration files using csync2 -xv before setup a service cluster.
* Don't use 255.255.255.0 mask format in Hawk web server wizard, use 24 instead.
* Set up clone resources for sbd, dlm(base) and ocfs, those must run on all nodes, or put them into a single group & clone.
* Configure constrains after resource creation, set up dependency(colocation) and order. (No need for Leap 42.1)