hashicorp/vagrant · error · Vagrant::Errors::NFSNoHostonlyNetwork

NFS requires a host-only network to be created. Please add a

Error message

NFS requires a host-only network to be created.
Please add a host-only network to the machine (with either DHCP or a
static IP) for NFS to work.

What it means

The Docker provider's PrepareNFSSettings computes NFS endpoints as the docker bridge IP (provider.driver.docker_bridge_ip, host side) and the machine's SSH host IP (provider.ssh_info[:host], guest side). If either is nil it raises NFSNoHostonlyNetwork before any mount is attempted - there is no usable host-guest network path for NFS.

Source

Thrown at plugins/providers/docker/action/prepare_nfs_settings.rb:52

          @machine.config.vm.synced_folders.any? { |_, opts| opts[:type] == :nfs }
        end

        def privileged_container?
          @machine.provider.driver.privileged?(@machine.id)
        end

        # Extracts the proper host and guest IPs for NFS mounts and stores them
        # in the environment for the SyncedFolder action to use them in
        # mounting.
        #
        # The ! indicates that this method modifies its argument.
        def add_ips_to_env!(env)
          provider = env[:machine].provider

          host_ip    = provider.driver.docker_bridge_ip
          machine_ip = provider.ssh_info[:host]

          raise Vagrant::Errors::NFSNoHostonlyNetwork if !host_ip || !machine_ip

          env[:nfs_host_ip]    = host_ip
          env[:nfs_machine_ip] = machine_ip
        end
      end
    end
  end
end

View on GitHub (pinned to 35f3160f4a)

Solutions

1. Ensure the machine is up and `vagrant ssh` works, then retry
2. Verify the default bridge exists (`ip addr show docker0`) and restore default daemon config if it was customized
3. If the bridge cannot be restored, switch the folder to a type that needs no host bridge, e.g. type: "rsync"

Example fix

# before
config.vm.synced_folder ".", "/vagrant", type: "nfs"

# after (no docker bridge available)
config.vm.synced_folder ".", "/vagrant", type: "rsync"

# NFS preflight for the docker provider
ip addr show docker0 >/dev/null 2>&1 || echo 'no docker0 bridge: NFS setup will fail'
vagrant ssh -c true >/dev/null 2>&1 || echo 'machine not reachable: bring it up first'

When it happens

Trigger: nfs synced folders on a docker-provider machine where the docker bridge cannot be detected (custom daemon config removing docker0) or ssh_info is unavailable because the container/host VM is not up or not reachable.

Common situations: Custom docker daemon with a renamed or removed default bridge; the NFS prepare step running before the machine is reachable; a broken host VM SSH connection.

Related errors

• The synced folder type '%{type}' is reporting as unusable fo
• The Docker provider is unable to connect the container to th
• The Docker provider was unable to configure networking using
• The configured network address is not valid within the confi
• The configured network subnet is not valid for the defined n

AI-assisted analysis of hashicorp/vagrant@35f3160f4a (2026-08-21). Data as JSON: /api/errors/91df8ddf1321a0e2. Report an issue: GitHub.