Refactor common modules.

CLAUDE.md

@@ -6,17 +6,23 @@ NixOS cluster configuration using flakes. Homelab infrastructure with Nomad/Cons
 
 ```
 ├── common/
-│   ├── global/          # Applied to all hosts (backup, sops, users, etc.)
-│   ├── compute-node.nix # Nomad client + Consul agent + NFS client
-│   ├── cluster-node.nix # Nomad server + Consul server (for quorum members)
-│   ├── nfs-services-server.nix   # NFS server + btrfs replication (zippy)
-│   └── nfs-services-standby.nix  # NFS standby + receive replication (c1, c2)
+│   ├── global/                    # Applied to all hosts (backup, sops, users, etc.)
+│   ├── minimal-node.nix           # Base (ssh, user, boot, impermanence)
+│   ├── cluster-member.nix         # Consul + storage clients (NFS/CIFS/GlusterFS)
+│   ├── nomad-worker.nix           # Nomad client (runs jobs) + Docker + NFS deps
+│   ├── nomad-server.nix           # Enables Consul + Nomad server mode
+│   ├── cluster-tools.nix          # Just CLI tools (nomad, wander, damon)
+│   ├── workstation-node.nix       # Dev tools (wget, deploy-rs, docker, nix-ld)
+│   ├── desktop-node.nix           # Hyprland + GUI environment
+│   ├── nfs-services-server.nix    # NFS server + btrfs replication (zippy)
+│   └── nfs-services-standby.nix   # NFS standby + receive replication (c1)
 ├── hosts/
-│   ├── c1/, c2/, c3/    # Cattle nodes (compute, quorum members)
-│   ├── zippy/           # Primary storage + NFS server + stateful workloads
+│   ├── c1/, c2/, c3/    # Cattle nodes (quorum + workers)
+│   ├── zippy/           # Primary storage + NFS server + worker (not quorum)
+│   ├── chilly/          # Home Assistant VM + cluster member (Consul only)
+│   ├── sparky/          # Desktop + cluster member (Consul only)
 │   ├── fractal/         # (Proxmox, will become NixOS storage node)
-│   ├── sunny/           # (Standalone ethereum node, not in cluster)
-│   └── chilly/          # (Home Assistant VM, not in cluster)
+│   └── sunny/           # (Standalone ethereum node, not in cluster)
 ├── docs/
 │   ├── CLUSTER_REVAMP.md    # Master plan for architecture changes
 │   ├── MIGRATION_TODO.md    # Tracking checklist for migration
@@ -35,11 +41,32 @@ NixOS cluster configuration using flakes. Homelab infrastructure with Nomad/Cons
 - `/data/shared` - CIFS from fractal (existing, unchanged)
 
 ### Hosts
-- **c1, c2, c3**: Cattle nodes, run most workloads, Nomad/Consul quorum
-- **zippy**: Primary NFS server, runs databases (affinity), replicates to c1 every 5min
+- **c1, c2, c3**: Cattle nodes, run most workloads, Nomad/Consul quorum members
+- **zippy**: Primary NFS server, runs workloads (affinity), NOT quorum, replicates to c1 every 5min
+- **chilly**: Home Assistant VM, cluster member (Consul agent + CLI tools), no workloads
+- **sparky**: Desktop/laptop, cluster member (Consul agent + CLI tools), no workloads
 - **fractal**: Storage node (Proxmox/ZFS), will join quorum after GlusterFS removed
-- **sunny**: Standalone ethereum staking node
-- **chilly**: Home Assistant VM
+- **sunny**: Standalone ethereum staking node (not in cluster)
+
+## Config Architecture
+
+**Modular role-based configs** (compose as needed):
+- `minimal-node.nix` - Base for all systems (SSH, user, boot, impermanence)
+- `cluster-member.nix` - Consul agent + shared storage mounts (no Nomad)
+- `nomad-worker.nix` - Nomad client to run jobs (requires cluster-member)
+- `nomad-server.nix` - Enables Consul + Nomad server mode (for quorum members)
+- `cluster-tools.nix` - Just CLI tools (no services)
+
+**Machine type configs** (via flake profile):
+- `workstation-node.nix` - Dev tools (deploy-rs, docker, nix-ld, emulation)
+- `desktop-node.nix` - Extends workstation + Hyprland/GUI
+
+**Host composition examples**:
+- c1/c2/c3: `cluster-member + nomad-worker + nomad-server` (quorum + runs jobs)
+- zippy: `cluster-member + nomad-worker` (runs jobs, not quorum)
+- chilly/sparky: `cluster-member + cluster-tools` (Consul + CLI only)
+
+**Key insight**: Profiles (workstation/desktop) no longer imply cluster membership. Hosts explicitly declare roles via imports.
 
 ## Key Patterns
 

README.md

@@ -42,7 +42,6 @@ Each layer extends the previous one, inheriting all configurations. Hosts select
 │   ├── desktop-node.nix      # Desktop layer: GUI environment
 │   ├── cloud-node.nix        # Cloud VPS profile
 │   ├── compute-node.nix      # Nomad worker profile
-│   ├── base-node.nix         # [DEPRECATED] Alias for cluster-node
 │   └── [feature modules]     # Individual feature configs
 ├── hosts/
 │   ├── c1/                   # Compute node 1

common/base-node.nix

@@ -1,8 +0,0 @@
-{ pkgs, ... }:
-{
-  # DEPRECATED: Use cluster-node.nix for cluster nodes or minimal-node.nix for minimal systems
-  # This file is kept for backward compatibility with existing configurations
-  imports = [
-    ./cluster-node.nix
-  ];
-}

common/compute-node.nix

@@ -1,10 +0,0 @@
-{ pkgs, ... }:
-{
-  # Compute node: Cluster node with Nomad and GlusterFS server
-  # Used by: c1, c2, c3
-  imports = [
-    ./cluster-node.nix
-    ./glusterfs.nix
-    ./nomad.nix
-  ];
-}

common/consul.nix

@@ -1,44 +1,47 @@
-{ pkgs, config, ... }:
+{ pkgs, config, lib, ... }:
 let
   servers = [
     "c1"
     "c2"
     "c3"
   ];
-  server_enabled = builtins.elem config.networking.hostName servers;
 in
 {
-  services.consul = {
-    enable = true;
-    webUi = true;
-    interface.advertise = "eno1";
-    extraConfig = {
-      client_addr = "0.0.0.0";
-      datacenter = "alo";
-      server = server_enabled;
-      bootstrap_expect = if server_enabled then (builtins.length servers + 2) / 2 else null;
-      retry_join = builtins.filter (elem: elem != config.networking.hostName) servers;
+  options.clusterRole.consulServer = lib.mkEnableOption "Consul server mode";
+
+  config = {
+    services.consul = {
+      enable = true;
+      webUi = true;
+      interface.advertise = "eno1";
+      extraConfig = {
+        client_addr = "0.0.0.0";
+        datacenter = "alo";
+        server = config.clusterRole.consulServer;
+        bootstrap_expect = if config.clusterRole.consulServer then (builtins.length servers + 2) / 2 else null;
+        retry_join = builtins.filter (elem: elem != config.networking.hostName) servers;
       telemetry = {
         prometheus_retention_time = "24h";
         disable_hostname = true;
       };
     };
-  };
+    };
 
-  environment.persistence."/persist".directories = [ "/var/lib/consul" ];
+    environment.persistence."/persist".directories = [ "/var/lib/consul" ];
 
-  networking.firewall = {
-    allowedTCPPorts = [
-      8600
-      8500
-      8301
-      8302
-      8300
-    ];
-    allowedUDPPorts = [
-      8600
-      8301
-      8302
-    ];
+    networking.firewall = {
+      allowedTCPPorts = [
+        8600
+        8500
+        8301
+        8302
+        8300
+      ];
+      allowedUDPPorts = [
+        8600
+        8301
+        8302
+      ];
+    };
   };
 }

common/nomad-server.nix

@@ -0,0 +1,9 @@
+{ ... }:
+{
+  # Enable server mode for both Consul and Nomad
+  # Used by: c1, c2, c3 (quorum members)
+  clusterRole = {
+    consulServer = true;
+    nomadServer = true;
+  };
+}

common/nomad-worker.nix

@@ -0,0 +1,9 @@
+{ ... }:
+{
+  # Enable Nomad client to run workloads
+  # Includes: Nomad client, Docker plugin, host volumes, NFS mount dependencies
+  # Used by: c1, c2, c3, zippy (all nodes that run Nomad jobs)
+  imports = [
+    ./nomad.nix
+  ];
+}

common/nomad.nix

@@ -1,174 +1,177 @@
 # inspiration: https://github.com/astro/skyflake/blob/main/nixos-modules/nomad.nix
-{ pkgs, config, ... }:
+{ pkgs, config, lib, ... }:
 let
   servers = [
     "c1"
     "c2"
     "c3"
   ];
-  server_enabled = builtins.elem config.networking.hostName servers;
 in
 {
-  services.nomad = {
-    enable = true;
-    # true breaks at least CSI volumes
-    # TODO: consider fixing
-    dropPrivileges = false;
+  options.clusterRole.nomadServer = lib.mkEnableOption "Nomad server mode";
 
-    settings = {
-      datacenter = "alo";
+  config = {
+    services.nomad = {
+      enable = true;
+      # true breaks at least CSI volumes
+      # TODO: consider fixing
+      dropPrivileges = false;
 
-      client = {
-        enabled = true;
-        server_join.retry_join = servers;
-        host_network.tailscale = {
-          interface = "tailscale0";
-          cidr = "100.64.0.0/10";
+      settings = {
+        datacenter = "alo";
+
+        client = {
+          enabled = true;
+          server_join.retry_join = servers;
+          host_network.tailscale = {
+            interface = "tailscale0";
+            cidr = "100.64.0.0/10";
+          };
+          host_volume = {
+            services = {
+              path = "/data/services";
+              read_only = false;
+            };
+            nix-store = {
+              path = "/nix/store";
+              read_only = true;
+            };
+            sw = {
+              path = "/run/current-system/sw";
+              read_only = true;
+            };
+          };
         };
-        host_volume = {
-          services = {
-            path = "/data/services";
-            read_only = false;
-          };
-          nix-store = {
-            path = "/nix/store";
-            read_only = true;
-          };
-          sw = {
-            path = "/run/current-system/sw";
-            read_only = true;
-          };
+
+        server = {
+          enabled = config.clusterRole.nomadServer;
+          bootstrap_expect = (builtins.length servers + 2) / 2;
+          server_join.retry_join = servers;
+        };
+
+        telemetry = {
+          collection_interval = "1s";
+          disable_hostname = true;
+          prometheus_metrics = true;
+          publish_allocation_metrics = true;
+          publish_node_metrics = true;
         };
       };
 
-      server = {
-        enabled = server_enabled;
-        bootstrap_expect = (builtins.length servers + 2) / 2;
-        server_join.retry_join = servers;
-      };
+      extraSettingsPaths = [ "/etc/nomad-alo.json" ];
+    };
 
-      telemetry = {
-        collection_interval = "1s";
-        disable_hostname = true;
-        prometheus_metrics = true;
-        publish_allocation_metrics = true;
-        publish_node_metrics = true;
+    # NFS mount dependency configuration for Nomad:
+    #
+    # Problem: Docker bind mounts need the real NFS mount, not an empty stub.
+    # If Nomad starts before NFS is mounted, containers get empty directories.
+    #
+    # Solution: Use soft dependencies (wants/after) with health-checking recovery.
+    # - wants: Nomad wants the mount, but won't be killed if it goes away
+    # - after: Nomad waits for mount to be attempted before starting
+    # - ExecStartPre with findmnt: Blocks Nomad start until mount is actually active
+    #
+    # This prevents Docker race conditions while allowing:
+    # - Boot to proceed if NFS unavailable (Nomad fails to start, systemd retries)
+    # - Nomad to keep running if NFS temporarily fails (containers may error)
+    # - Recovery service to auto-restart Nomad when NFS comes back or becomes stale
+    #
+    # Note: Mount uses Consul DNS which resolves at mount time. If NFS server
+    #       moves to different IP, mount becomes stale and needs remount.
+    #       The recovery service handles this by detecting stale mounts and restarting Nomad.
+    systemd.services.nomad = {
+      wants = [ "network-online.target" "data-services.mount" ];
+      after = [ "data-services.mount" ];
+      serviceConfig.ExecStartPre = "${pkgs.util-linux}/bin/findmnt --mountpoint /data/services";
+    };
+
+    # Recovery service: automatically restart Nomad when NFS mount needs attention
+    # This handles scenarios where:
+    # - NFS server was down during boot (mount failed, Nomad hit start-limit)
+    # - NFS server failed over to different host with new IP (mount went stale)
+    # - Network outage temporarily broke the mount
+    #
+    # The timer runs every 30s and checks:
+    # 1. Is mount healthy (exists and accessible)?
+    # 2. If mount is stale/inaccessible → restart Nomad (triggers remount)
+    # 3. If mount is healthy but Nomad failed → restart Nomad (normal recovery)
+    systemd.services.nomad-mount-watcher = {
+      description = "Restart Nomad when NFS mount needs attention";
+      serviceConfig = {
+        Type = "oneshot";
+        ExecStart = pkgs.writeShellScript "nomad-mount-watcher" ''
+          # Check if mount point exists
+          if ! ${pkgs.util-linux}/bin/findmnt --mountpoint /data/services >/dev/null 2>&1; then
+            exit 0  # Mount not present, nothing to do
+          fi
+
+          # Check if mount is actually accessible (not stale)
+          # Use timeout to avoid hanging on stale NFS mounts
+          if ! ${pkgs.coreutils}/bin/timeout 5s ${pkgs.coreutils}/bin/stat /data/services >/dev/null 2>&1; then
+            echo "NFS mount is stale or inaccessible. Restarting Nomad to trigger remount..."
+            ${pkgs.systemd}/bin/systemctl restart nomad.service
+            exit 0
+          fi
+
+          # Mount is healthy - check if Nomad needs recovery
+          if ${pkgs.systemd}/bin/systemctl is-failed nomad.service >/dev/null 2>&1; then
+            echo "NFS mount is healthy but Nomad is failed. Restarting Nomad..."
+            ${pkgs.systemd}/bin/systemctl restart nomad.service
+          fi
+        '';
       };
     };
 
-    extraSettingsPaths = [ "/etc/nomad-alo.json" ];
-  };
-
-  # NFS mount dependency configuration for Nomad:
-  #
-  # Problem: Docker bind mounts need the real NFS mount, not an empty stub.
-  # If Nomad starts before NFS is mounted, containers get empty directories.
-  #
-  # Solution: Use soft dependencies (wants/after) with health-checking recovery.
-  # - wants: Nomad wants the mount, but won't be killed if it goes away
-  # - after: Nomad waits for mount to be attempted before starting
-  # - ExecStartPre with findmnt: Blocks Nomad start until mount is actually active
-  #
-  # This prevents Docker race conditions while allowing:
-  # - Boot to proceed if NFS unavailable (Nomad fails to start, systemd retries)
-  # - Nomad to keep running if NFS temporarily fails (containers may error)
-  # - Recovery service to auto-restart Nomad when NFS comes back or becomes stale
-  #
-  # Note: Mount uses Consul DNS which resolves at mount time. If NFS server
-  #       moves to different IP, mount becomes stale and needs remount.
-  #       The recovery service handles this by detecting stale mounts and restarting Nomad.
-  systemd.services.nomad = {
-    wants = [ "network-online.target" "data-services.mount" ];
-    after = [ "data-services.mount" ];
-    serviceConfig.ExecStartPre = "${pkgs.util-linux}/bin/findmnt --mountpoint /data/services";
-  };
-
-  # Recovery service: automatically restart Nomad when NFS mount needs attention
-  # This handles scenarios where:
-  # - NFS server was down during boot (mount failed, Nomad hit start-limit)
-  # - NFS server failed over to different host with new IP (mount went stale)
-  # - Network outage temporarily broke the mount
-  #
-  # The timer runs every 30s and checks:
-  # 1. Is mount healthy (exists and accessible)?
-  # 2. If mount is stale/inaccessible → restart Nomad (triggers remount)
-  # 3. If mount is healthy but Nomad failed → restart Nomad (normal recovery)
-  systemd.services.nomad-mount-watcher = {
-    description = "Restart Nomad when NFS mount needs attention";
-    serviceConfig = {
-      Type = "oneshot";
-      ExecStart = pkgs.writeShellScript "nomad-mount-watcher" ''
-        # Check if mount point exists
-        if ! ${pkgs.util-linux}/bin/findmnt --mountpoint /data/services >/dev/null 2>&1; then
-          exit 0  # Mount not present, nothing to do
-        fi
-
-        # Check if mount is actually accessible (not stale)
-        # Use timeout to avoid hanging on stale NFS mounts
-        if ! ${pkgs.coreutils}/bin/timeout 5s ${pkgs.coreutils}/bin/stat /data/services >/dev/null 2>&1; then
-          echo "NFS mount is stale or inaccessible. Restarting Nomad to trigger remount..."
-          ${pkgs.systemd}/bin/systemctl restart nomad.service
-          exit 0
-        fi
-
-        # Mount is healthy - check if Nomad needs recovery
-        if ${pkgs.systemd}/bin/systemctl is-failed nomad.service >/dev/null 2>&1; then
-          echo "NFS mount is healthy but Nomad is failed. Restarting Nomad..."
-          ${pkgs.systemd}/bin/systemctl restart nomad.service
-        fi
-      '';
-    };
-  };
-
-  systemd.timers.nomad-mount-watcher = {
-    description = "Timer for Nomad mount watcher";
-    wantedBy = [ "timers.target" ];
-    timerConfig = {
-      OnBootSec = "1min";       # First run 1min after boot
-      OnUnitActiveSec = "30s";  # Then every 30s
-      Unit = "nomad-mount-watcher.service";
-    };
-  };
-
-  environment.etc."nomad-alo.json".text = builtins.toJSON {
-    plugin.docker.config = {
-      allow_privileged = true;
-      # for keepalived, though only really needing "NET_ADMIN","NET_BROADCAST","NET_RAW" on top of default
-      # TODO: trim this down
-      allow_caps = [ "all" ];
-      volumes.enabled = true;
-      extra_labels = [
-        "job_name"
-        "task_group_name"
-        "task_name"
-        "node_name"
-      ];
+    systemd.timers.nomad-mount-watcher = {
+      description = "Timer for Nomad mount watcher";
+      wantedBy = [ "timers.target" ];
+      timerConfig = {
+        OnBootSec = "1min";       # First run 1min after boot
+        OnUnitActiveSec = "30s";  # Then every 30s
+        Unit = "nomad-mount-watcher.service";
+      };
     };
 
-    plugin.raw_exec.config.enabled = true;
-  };
+    environment.etc."nomad-alo.json".text = builtins.toJSON {
+      plugin.docker.config = {
+        allow_privileged = true;
+        # for keepalived, though only really needing "NET_ADMIN","NET_BROADCAST","NET_RAW" on top of default
+        # TODO: trim this down
+        allow_caps = [ "all" ];
+        volumes.enabled = true;
+        extra_labels = [
+          "job_name"
+          "task_group_name"
+          "task_name"
+          "node_name"
+        ];
+      };
 
-  environment.persistence."/persist".directories = [
-    "/var/lib/docker"
-    "/var/lib/nomad"
-  ];
+      plugin.raw_exec.config.enabled = true;
+    };
 
-  environment.systemPackages = with pkgs; [
-    nomad
-    wander
-    damon
-  ];
+    environment.persistence."/persist".directories = [
+      "/var/lib/docker"
+      "/var/lib/nomad"
+    ];
 
-  networking.firewall = {
-    allowedTCPPorts =
-      if server_enabled then
-        [
-          4646
-          4647
-          4648
-        ]
-      else
-        [ 4646 ];
-    allowedUDPPorts = if server_enabled then [ 4648 ] else [ ];
+    environment.systemPackages = with pkgs; [
+      nomad
+      wander
+      damon
+    ];
+
+    networking.firewall = {
+      allowedTCPPorts =
+        if config.clusterRole.nomadServer then
+          [
+            4646
+            4647
+            4648
+          ]
+        else
+          [ 4646 ];
+      allowedUDPPorts = if config.clusterRole.nomadServer then [ 4648 ] else [ ];
+    };
   };
 }

common/server-node.nix

@@ -1,14 +0,0 @@
-{ pkgs, ... }:
-{
-  # Server profile: Cluster-enabled system for server deployments
-  # Extends cluster-node with server-specific configurations
-  # Future: Add bare NixOS services here (mysql, postgres, etc.) when migrating from Nomad
-  imports = [
-    ./cluster-node.nix
-  ];
-
-  # Server-specific configurations can be added here
-  # Example (for future use):
-  # services.mysql.enable = lib.mkDefault false;
-  # services.postgresql.enable = lib.mkDefault false;
-}

common/sshd.nix

@@ -3,8 +3,6 @@
     enable = true;
     allowSFTP = true;
     settings = {
-      PasswordAuthentication = false;
-      KbdInteractiveAuthentication = false;
       PermitRootLogin = "prohibit-password";  # Allow root login with SSH keys only
     };
   };

common/workstation-node.nix

@@ -1,9 +1,9 @@
 { pkgs, inputs, ... }:
 {
   # Workstation profile: Development workstation configuration
-  # Extends server-node with development tools and emulation
+  # Adds development tools and emulation on top of minimal-node
   imports = [
-    ./server-node.nix
+    ./minimal-node.nix
     ./unattended-encryption.nix
   ];
 

flake.nix

@@ -140,7 +140,7 @@
         c2 = mkHost "x86_64-linux" "server" [ ./hosts/c2 ];
         c3 = mkHost "x86_64-linux" "server" [ ./hosts/c3 ];
         alo-cloud-1 = mkHost "aarch64-linux" "cloud" [ ./hosts/alo-cloud-1 ];
-        zippy = mkHost "x86_64-linux" "workstation" [
+        zippy = mkHost "x86_64-linux" "minimal" [
           ethereum-nix.nixosModules.default
           ./hosts/zippy
         ];

hosts/c1/default.nix

@@ -3,7 +3,10 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
-    ../../common/compute-node.nix
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/nomad-worker.nix     # Nomad client (runs jobs)
+    ../../common/nomad-server.nix     # Consul + Nomad server mode
+    ../../common/glusterfs.nix        # GlusterFS server (temp during migration)
     ../../common/nfs-services-standby.nix  # NFS standby for /data/services
     # To promote to NFS server (during failover):
     # 1. Follow procedure in docs/NFS_FAILOVER.md

hosts/c2/default.nix

@@ -3,7 +3,10 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
-    ../../common/compute-node.nix
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/nomad-worker.nix     # Nomad client (runs jobs)
+    ../../common/nomad-server.nix     # Consul + Nomad server mode
+    ../../common/glusterfs.nix        # GlusterFS server (temp during migration)
     ./hardware.nix
   ];
 

hosts/c3/default.nix

@@ -3,7 +3,10 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
-    ../../common/compute-node.nix
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/nomad-worker.nix     # Nomad client (runs jobs)
+    ../../common/nomad-server.nix     # Consul + Nomad server mode
+    ../../common/glusterfs.nix        # GlusterFS server (temp during migration)
     ../../common/binary-cache-server.nix
     ./hardware.nix
   ];

hosts/chilly/default.nix

@@ -8,6 +8,8 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/cluster-tools.nix    # Nomad CLI (no service)
     ./hardware.nix
   ];
 

hosts/sparky/default.nix

@@ -3,6 +3,8 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/cluster-tools.nix    # Nomad CLI (no service)
     ./hardware.nix
   ];
 

hosts/zippy/default.nix

@@ -3,7 +3,10 @@
   imports = [
     ../../common/encrypted-btrfs-layout.nix
     ../../common/global
-    ../../common/compute-node.nix
+    ../../common/cluster-member.nix  # Consul + storage clients
+    ../../common/nomad-worker.nix     # Nomad client (runs jobs)
+    # NOTE: zippy is NOT a server - no nomad-server.nix import
+    ../../common/glusterfs.nix        # GlusterFS server (temp during migration)
 #    ../../common/ethereum.nix
     ../../common/nfs-services-server.nix  # NFS server for /data/services
     # To move NFS server role to another host: