corosync-blackbox Trigger corosync to write it's "flight data" out to file and then run qb-blackbox which prints it out.
- Print the current "flight data".
Starting replay: head  tail 
rec= Log Message=Corosync Cluster Engine ('1.2.1'): started and ready to provide service.
rec= Log Message=Delivering MCAST message with seq a to pending delivery queue
rec= Log Message=downlist received left_list: 2
rec= Log Message=chosen downlist from node r(0) ip(192.168.100.11)
Finishing replay: records found