location cli-prefer-virtip virtip role=Started inf: msnode1
this means that you have run the "crm resource migrate virtip msnode1". When node1 dies - it will migrate to node2 and then when node1 is back - it will recover on node1.

Remove it by using "crm resource unmigrate virtip " and it will remove the cli-prefer.

Also, consider adding fencing mechanism - either SBD or any other type in order to guarantee that resources will be failed over.

Another issue:

Current DC: msnode2 (version 1.1.16-4.8-77ea74d) - partition WITHOUT quorum
you need the "two_node:1 " set on both nodes (use csync2 -m /etc/corosync/corosync.conf ; csync2 -x to sync it between nodes)

Note , as the two_node is enabled it will automatically enable "wait_for_all" which means that if both nodes die (power outage , double fencing anything outstanding), then both nodes should be started before any resource is taken.
I would recommend it to leave it by default ,as you don't have a fencing mechanism and you could have the IP and the service started on both nodes - which is bad.