How to open a specific port such as 9090 in Google Compute Engine

Question

I have 2 Google Compute Engine instances and I want to open port 9090 in both the instances. I think we need to add some firewall rules.

Can you tell me how can I

Answer 1

console.cloud.google.com >> select project >> Networking > VPC network >> firewalls >> create firewall.

To apply the rule to VM instances, select Targets, "Specified target tags", and enter into "Target tags" the name of the tag. This tag will be used to apply the new firewall rule onto whichever instance you'd like.

in "Protocols and Ports" enter tcp:9090

Click Save.