Locate the DB2 connection port number on Linux

1)Open a DB2 command prompt

2)Verify you are on the correct instance

   db2 get instance

3)Find the service name of your instance

   db2 get dbm cfg | grep SVCE

You'll get back something like :

TCP/IP Service Name     (SVCENAME) = db2mydb2

4)Use the service name to find the port number in the services file
e.g

grep <my service> /etc/services

you'll get back something like

<my service > 50000/tcp

Read More on DB2 list schemas, connections, db2expln

DB2 list schemas of a database - DBA DB2

Force connections of a database in DB2

DB2 Query Tuning – db2expln