Getting "Name or service not known" error when using podman-compose

Question

I'm trying to build a podman compose file that uses nfs volumes for my containers. I can mount the volume in the container just find if I invoke it on the command line with "podman run -v", but if I put it in the file as below and run podman-compose, I guet the "name or service not known" error.

webui:
  image: utopia:5000/webui:194231672452
  networks:
    webui:
      ipv4_address: 172.17.0.7
  volumes:
    - sw:/sw

volumes:
  sw:
    driver: local
    driver_opts:
    type: nfs
    o: rw,nfsvers=3
    device: "treant:/vol/sw/sw

I expect the volume to be nfs-mounted inside the container. Update: I had a dangling volume with old options, deleting that made this go away.