modules.openafsServer: Add FABS backup server

1 files changed, 68 insertions, 18 deletions

diff --git a/nixos/modules/services/network-filesystems/openafs/server.nix b/nixos/modules/services/network-filesystems/openafs/server.nix
index 1c615d3bfb6..ad0fd783567 100644
--- a/nixos/modules/services/network-filesystems/openafs/server.nix
+++ b/nixos/modules/services/network-filesystems/openafs/server.nix
@@ -4,7 +4,8 @@
 with import ./lib.nix { inherit config lib pkgs; };
 
 let
-  inherit (lib) concatStringsSep literalExpression mkIf mkOption optionalString types;
+  inherit (lib) concatStringsSep literalExpression mkIf mkOption mkEnableOption
+  optionalString types;
 
   bosConfig = pkgs.writeText "BosConfig" (''
     restrictmode 1
@@ -24,9 +25,15 @@ let
     parm ${openafsSrv}/libexec/openafs/salvageserver ${cfg.roles.fileserver.salvageserverArgs}
     parm ${openafsSrv}/libexec/openafs/dasalvager ${cfg.roles.fileserver.salvagerArgs}
     end
-  '') + (optionalString (cfg.roles.database.enable && cfg.roles.backup.enable) ''
+  '') + (optionalString (cfg.roles.database.enable && cfg.roles.backup.enable && (!cfg.roles.backup.enableFabs)) ''
     bnode simple buserver 1
-    parm ${openafsSrv}/libexec/openafs/buserver ${cfg.roles.backup.buserverArgs} ${optionalString (cfg.roles.backup.cellServDB != []) "-cellservdb /etc/openafs/backup/"}
+    parm ${openafsSrv}/libexec/openafs/buserver ${cfg.roles.backup.buserverArgs} ${optionalString useBuCellServDB "-cellservdb /etc/openafs/backup/"}
+    end
+  '') + (optionalString (cfg.roles.database.enable &&
+                         cfg.roles.backup.enable &&
+                         cfg.roles.backup.enableFabs) ''
+    bnode simple buserver 1
+    parm ${lib.getBin pkgs.fabs}/bin/fabsys server --config ${fabsConfFile} ${cfg.roles.backup.fabsArgs}
     end
   ''));
 
@@ -34,12 +41,27 @@ let
     pkgs.writeText "NetInfo" ((concatStringsSep "\nf " cfg.advertisedAddresses) + "\n")
   else null;
 
-  buCellServDB = pkgs.writeText "backup-cellServDB-${cfg.cellName}" (mkCellServDB cfg.cellName cfg.roles.backup.cellServDB);
+  buCellServDB = pkgs.writeText "backup-cellServDB-${cfg.cellName}"
+    (mkCellServDB cfg.cellName cfg.roles.backup.cellServDB);
+
+  useBuCellServDB = (cfg.roles.backup.cellServDB != []) && (!cfg.roles.backup.enableFabs);
 
   cfg = config.services.openafsServer;
 
   udpSizeStr = toString cfg.udpPacketSize;
 
+  fabsConfFile = pkgs.writeText "fabs.yaml" (builtins.toJSON ({
+    afs = {
+      aklog = cfg.package + "/bin/aklog";
+      cell = cfg.cellName;
+      dumpscan = cfg.package + "/bin/afsdump_scan";
+      fs = cfg.package + "/bin/fs";
+      pts = cfg.package + "/bin/pts";
+      vos = cfg.package + "/bin/vos";
+    };
+    k5start.command = (lib.getBin pkgs.kstart) + "/bin/k5start";
+  } // cfg.roles.backup.fabsExtraConfig));
+
 in {
 
   options = {
@@ -80,8 +102,8 @@ in {
       };
 
       package = mkOption {
-        default = pkgs.openafs.server or pkgs.openafs;
-        defaultText = literalExpression "pkgs.openafs.server or pkgs.openafs";
+        default = pkgs.openafs;
+        defaultText = literalExpression "pkgs.openafs";
         type = types.package;
         description = lib.mdDoc "OpenAFS package for the server binaries";
       };
@@ -154,16 +176,20 @@ in {
         };
 
         backup = {
-          enable = mkOption {
-            default = false;
-            type = types.bool;
-            description = lib.mdDoc ''
-              Backup server role. Use in conjunction with the
-              `database` role to maintain the Backup
-              Database. Normally only used in conjunction with tape storage
-              or IBM's Tivoli Storage Manager.
-            '';
-          };
+          enable = mkEnableOption (lib.mdDoc ''
+            Backup server role. When using OpenAFS built-in buserver, use in conjunction with the
+            `database` role to maintain the Backup
+            Database. Normally only used in conjunction with tape storage
+            or IBM's Tivoli Storage Manager.
+
+            For a modern backup server, enable this role and see
+            {option}`enableFabs`.
+          '');
+
+          enableFabs = mkEnableOption (lib.mdDoc ''
+            FABS, the flexible AFS backup system. It stores volumes as dump files, relying on other
+            pre-existing backup solutions for handling them.
+          '');
 
           buserverArgs = mkOption {
             default = "";
@@ -181,6 +207,30 @@ in {
               other database server machines.
             '';
           };
+
+          fabsArgs = mkOption {
+            default = "";
+            type = types.str;
+            description = lib.mdDoc ''
+              Arguments to the fabsys process. See
+              {manpage}`fabsys_server(1)` and
+              {manpage}`fabsys_config(1)`.
+            '';
+          };
+
+          fabsExtraConfig = mkOption {
+            default = {};
+            type = types.attrs;
+            description = lib.mdDoc ''
+              Additional configuration parameters for the FABS backup server.
+            '';
+            example = literalExpression ''
+            {
+              afs.localauth = true;
+              afs.keytab = config.sops.secrets.fabsKeytab.path;
+            }
+            '';
+          };
         };
       };
 
@@ -239,7 +289,7 @@ in {
         mode = "0644";
       };
       buCellServDB = {
-        enable = (cfg.roles.backup.cellServDB != []);
+        enable = useBuCellServDB;
         text = mkCellServDB cfg.cellName cfg.roles.backup.cellServDB;
         target = "openafs/backup/CellServDB";
       };
@@ -257,7 +307,7 @@ in {
         preStart = ''
           mkdir -m 0755 -p /var/openafs
           ${optionalString (netInfo != null) "cp ${netInfo} /var/openafs/netInfo"}
-          ${optionalString (cfg.roles.backup.cellServDB != []) "cp ${buCellServDB}"}
+          ${optionalString useBuCellServDB "cp ${buCellServDB}"}
         '';
         serviceConfig = {
           ExecStart = "${openafsBin}/bin/bosserver -nofork";