diff --git a/lib/charms/mongodb/v0/helpers.py b/lib/charms/mongodb/v0/helpers.py
index ec7eaeaf4..d4c820aaa 100644
--- a/lib/charms/mongodb/v0/helpers.py
+++ b/lib/charms/mongodb/v0/helpers.py
@@ -91,8 +91,9 @@ def get_mongos_args(config: MongoDBConfiguration) -> str:
     # no need to add TLS since no network calls are used, since mongos is configured to listen
     # on local host
     cmd = [
-        # mongos on config server side only runs on local host
-        "--bind_ip localhost",
+        # mongos on config server side should run on 0.0.0.0 so it can be accessed by other units
+        # in the sharded cluster
+        "--bind_ip 0.0.0.0",
         # todo figure out this one
         f"--configdb {config_server_uri}",
         # config server is already using 27017