diff --git a/openstack_operator/memcached.py b/openstack_operator/memcached.py
index e3262516..6d01397c 100644
--- a/openstack_operator/memcached.py
+++ b/openstack_operator/memcached.py
@@ -66,7 +66,7 @@ def deployment_event(namespace, meta, spec, **_):
     name = meta['labels']['app.kubernetes.io/instance']
     selector = spec['selector']['matchLabels']
     servers = utils.get_ready_pod_ips(namespace, selector)
-    memcacheds = ["%s:11211" for s in servers]
+    memcacheds = ["%s:11211" % s for s in servers]
 
     utils.create_or_update('memcached/mcrouter.yml.j2',
                            name=name, servers=memcacheds,