Inter-subnet communication within the same VPC

[ennovers1]

Hello Community, 

I am fairly new to GCP networking and I could use some guidance. I'm sure there is a simple explanation for what I'd like to accomplish.  I believe its just a simple firewall rule but I'm not sure how to configure the rule.

I current have 3 subnets in the same VPC network. I'd like subnet-a to be a "jump-network" for admins doing work on compute instances in subnet-b and subnet-c over various ports. i.e. 22, 3389, 80, 443 etc etc. Admins will work on a jump VM (windows) in subnet-a and access compute instances (both windows/linux) in subnet-b and subnet-c. (using private IP addresses)

I'm sure there are simple firewall rules to allow connectivity between subnets inside the same VPC. Can someone help me? What are the firewall rules? 

Thanks. Any and all input from the community is greatly appreciated.  

[VishalBulbule]

Hi @ennovers1 

You need to create firewall rule with target on all vm instance or using tag and source range you can give for subnet-a. So it will allow any traffice in your vpc from subnet-a 

Refer below video

https://youtu.be/m3Ts42FSYh8

[kumards]

Hi @ennovers1 ,

Welcome to Google Cloud, and I wish you a smooth journey in our cloud!

The default VPC network (which is auto-created for a new project) has pre-defined firewall rules that allow traffic between the subnets of the VPC.

For any VPC network that you created, firewall rules are auto-created to deny all ingress traffic and allow all egress traffic. While creating the VPC network (in the console), you're presented with an option to create/edit ingress rules to allow inter-subnet traffic on all ports or specific ports of your choice, as shown in this screenshot:

At any time after creating the VPC network, you can create/edit firewall rules as necessary.