Make the Loki that ships with NixOS 21.11 work

nixos/modules/monitoring/exporters/promtail.nix

@@ -13,7 +13,7 @@
     server = {
       http_listen_port = 9080; # Using /metrics for health check
       grpc_listen_address = "127.0.0.1"; # unused, but no option to turn it off.
-      grpc_listen_port = 9095; # unused, but no option to turn it off.
+      grpc_listen_port = 9094; # unused, but no option to turn it off.
     };
 
     clients = [{

nixos/modules/monitoring/server/loki.nix

@@ -24,7 +24,6 @@
 
         ingester = {
           lifecycler = {
-            interface_names = [ "monitoringvpn"];
             ring = {
               kvstore = {
                 store = "inmemory";
@@ -59,10 +58,6 @@
           };
         };
 
-        chunk_store_config = {
-          max_look_back_period = "336h"; # two weeks
-        };
-
         table_manager = {
           retention_deletes_enabled = true;
           retention_period = "336h"; # two weeks