Problem joining Consul cluster on GCP


I’m running terraform-google-consul/modules/consul-cluster at master · hashicorp/terraform-google-consul · GitHub on GCP and the Consul servers/clients cannot find each other unless I make all the IPs public.
The VMs are reachable from each other when I tried to ping them when I use the private IPs. I also tried to fully open the firewall and nothing changed.

The only real change I did was to switch the region instance manager for a normal manager.

Thank you for your answers