Session ID Format in Command Output
The output of the show sessions command displays the session ID in the following format:
ssssssss:tt
ssssssss
Is the session ID
tt
Is the thread ID (for DBMS and recovery servers) or the GCA association ID (for GCF servers).
In the example 8125620:2, the notation :2 is the GCA association ID specific to the given server, when available. This ID may also be shown in error logs and trace output.
Note: The association ID in one server (for example, Name Server) does not necessarily match the association ID in another server (for example, Communications Server).