add first step backup for kabtop

hosts/jupiter/hardware-configuration.nix

@@ -113,6 +113,35 @@
           };
         };
       };
+      remote = {
+        onCalendar = "weekly";
+        settings = {
+          stream_buffer = "265m";
+          stream_compress = "lz4";
+          incremental = "yes";
+          snapshot_create = "no";
+          snapshot_dir = "@snapshots";
+          timestamp_format = "long";
+
+          snapshot_preserve_min = "all";
+          target_preserve_min = "no";
+          target_preserve = "4w 2m";
+          archive_preserve_min = "no";
+          archive_preserve = "4w 2m";
+
+          ssh_identity = "/etc/btrbk/ssh/id_ed25519_btrbk_remote";
+          ssh_user = "btrbk";
+
+          volume = {
+            "ssh://prepaid-big.kabtop.de:2220/mnt/snapshots/root" = {
+              target = "/mnt/snapshots/Pluto/@snapshots/@kabtop";
+              subvolume = {
+                "@/var" = {};
+              };
+            };
+          };
+        };
+      };
     };
   };