CSID
A CSID, or a Cluster System Identification Number, is a number that uniquely identifies a node in an OpenVMS Cluster. It is assigned to the node when the node enters a cluster. An example of a CSID is '10010'.
To display CSID of all systems in a cluster, use the SHOW CLUSTER/CONTINUOUS CSID field in the MEMBERS class.
You can find out the CSID of a F$CONTEXT context using the F$CSID() lexical function.
