diff --git a/src/config.yaml b/src/config.yaml
index 66b77bc..625eefd 100644
--- a/src/config.yaml
+++ b/src/config.yaml
@@ -44,3 +44,11 @@ options:
         Time (in seconds) until the cache becomes invalid if not refreshed.
         Defaults to -1 (infinite). The value must be larger than
         auth_cache_refresh_interval else Router won't start.
+  max_connections:
+    type: int
+    default: 512
+    description: |
+        Maximum number of connections to allow in direction to each MySQL
+        routing sessions, with one for the RW unit and another one for the RO
+        units of the MySQL innodb cluster. Defaults to 512. A valid range is
+        between 1 and 65535.
diff --git a/src/lib/charm/openstack/mysql_router.py b/src/lib/charm/openstack/mysql_router.py
index 72ee60c..71583b3 100644
--- a/src/lib/charm/openstack/mysql_router.py
+++ b/src/lib/charm/openstack/mysql_router.py
@@ -673,6 +673,7 @@ class MySQLRouterCharm(charms_openstack.charm.OpenStackCharm):
             },
             "DEFAULT": {
                 "pid_file": self.mysqlrouter_pid_file,
+                "max_connections": str(self.options.max_connections),
             }
         }
 
diff --git a/unit_tests/test_lib_charm_openstack_mysql_router.py b/unit_tests/test_lib_charm_openstack_mysql_router.py
index 943969d..15e6b8c 100644
--- a/unit_tests/test_lib_charm_openstack_mysql_router.py
+++ b/unit_tests/test_lib_charm_openstack_mysql_router.py
@@ -695,6 +695,7 @@ class TestMySQLRouterCharm(test_utils.PatchHelper):
             "ttl": '5',
             "auth_cache_ttl": '10',
             "auth_cache_refresh_interval": '7',
+            "max_connections": '1000',
         }
 
         def _fake_config(key=None):
@@ -711,10 +712,13 @@ class TestMySQLRouterCharm(test_utils.PatchHelper):
         mrc.name = 'foobar'
         mrc.update_config_parameters = _mock_update_config_parameters
 
+        _metadata_config = _config_data.copy()
+        _metadata_config.pop('max_connections')
         _params = {
-            'metadata_cache:jujuCluster': _config_data,
+            'metadata_cache:jujuCluster': _metadata_config,
             'DEFAULT': {
                 'client_ssl_mode': "PASSTHROUGH",
+                'max_connections': _config_data['max_connections'],
                 'pid_file': '/run/mysql/mysqlrouter-foobar.pid'
             },
         }