In today's virtualized environment, it is easier to clone a virtual machine from an existing one.
When DB2 is already installed with Tivoli SA MP for high availability, we need to also make sure that each host has a unique node id otherwise HA configuration will fail due to the identical node id.
Check the unique node id by looking at /etc/ct_node_id and it should show unique value and of course this will not be the case when machines are cloned in a virtual environment.
You can run the command recfgct to regenarate this number on each cloned host.
/usr/sbin/rsct/install/bin/recfgct
You can also use /usr/sbin/rsct/mknodeid -f to regenerate the node id alone but using recfgct is preferred as it does all related things also.