How to solve: Db2 is not listening port problem

Sometimes a mistake made by db administrator causes that kind of problem.

 

To solve this problem we need to take a few simple steps and check system services.

First of all, you need to get database service configuration with this command:

Does that value empty? You need to set a port number to test (we will change it with service name)

Now you should find an empty port, for example 55000. Let’s find if it is in use:

That command must return an empty result set. If it returns a row, you need to choose a different port.

Stop db2 and update your configuration for port 55000

Now start db2 and check does db2 listening port 55000.

You MUST see port 55000 is actively listening. If you can confirm that, db2 is listening 55000, jump to Modifying /etc/services section.

If port 55000 still is not in the list you need to update db2 system variables via that simple commands.

Last command lists db2 system variables. DB2COMM must be set to TCPIP to listen TCP ports.

Modifying /etc/services 

Most of *nix system users are familiar with /etc/services file. In *nix systems, service names and their port and protocol are stored in this file.

We have a simple template to add db2 service to end of this file.

db2c_<instance_name>      <port_number>/tcp  #db2 service port

Open that file via vi (or your favorite text editor) and add your db2c_…. row to end of /etc/services.

And now, you must update db2 configuration with your new service name:

Do not forget to change <instance_name> with your db2 instance name.

Confirm that db2 is listening port in /etc/services.