diff --git a/modules/base/zfsborg/default.nix b/modules/base/zfsborg/default.nix
index b9d6d19..76694cf 100644
--- a/modules/base/zfsborg/default.nix
+++ b/modules/base/zfsborg/default.nix
@@ -92,6 +92,9 @@ in {
                     weekly = 4;
                     monthly = 3;
                   };
+                  environment.BORG_HOST_ID = let
+                    h = config.networking;
+                  in "${h.hostName}.${h.domain}@${h.hostId}";
                 }
                 // lib.optionalAttrs (attrs ? patterns) {
                   patterns = attrs.patterns;