After I have already uploaded the appliance, how do I permanently change the gw?

At the beginning of the installation of ESRS 3.40 (Linux), we put the wrong gw. Despite this, we managed to get to the end of the installation because the wrong gw is one that is between the servers; only we wanted to make a direct call on the correct gw. What is the most correct way to change gw now? Can I do this simply as below, that there will be no problem?

/ etc / sysconfig / network / routes file.

default - -