diff --git a/roles/nagios_client/templates/check_mailman_api.cfg.j2 b/roles/nagios_client/templates/check_mailman_api.cfg.j2
index 95213f335f..c6ce15f366 100644
--- a/roles/nagios_client/templates/check_mailman_api.cfg.j2
+++ b/roles/nagios_client/templates/check_mailman_api.cfg.j2
@@ -1 +1 @@
-command[check_mailman_api]=/usr/lib64/nagios/plugins/check_http -H localhost -p 8001 -u /3.0 -e 'HTTP/1.0 401 Unauthorized'
+command[check_mailman_api]=/usr/lib64/nagios/plugins/check_http -H localhost -p 8001 -u /3.0 -e 'HTTP/1.1 401 Unauthorized'