diff --git a/modules/monitoring/server.nix b/modules/monitoring/server.nix
index 37a2afa..9470b1d 100644
--- a/modules/monitoring/server.nix
+++ b/modules/monitoring/server.nix
@@ -29,6 +29,9 @@ in
     enable = true;
     listenAddress = "127.0.0.1:${toString vmPort}";
     retentionPeriod = "180d";
+    # The scraper dials IPv4-only by default; our ns1/ns2 targets are mesh ULAs,
+    # so without this VM drops them with "no suitable address found (try -enableTCP6)".
+    extraOptions = [ "-enableTCP6" ];
     prometheusConfig = {
       global.scrape_interval = "30s";
       scrape_configs = [