If one clones the slurm-gcp project and deploys the stock cluster defined in there, things work well.
What I would like to do, is to use a GCP Filestore instance to provide (more) persistent storage to the cluster.
Part of the cluster deployment is to create a VPC network (and a subnetwork) called g1-network.
If I, after the cluster has deployed successfully, create a Filestore instance, I can select the g1-network. I can see that suitable routes are created. But I can't ping the Filestore instance from any of the cluster machines.