diff --git a/roles/mongodb/templates/mongod.conf.j2 b/roles/mongodb/templates/mongod.conf.j2
index 9d9c9c9c1..958c4a50e 100644
--- a/roles/mongodb/templates/mongod.conf.j2
+++ b/roles/mongodb/templates/mongod.conf.j2
@@ -5,7 +5,8 @@
 # Comma separated list of ip addresses to listen on (all local ips by default)
 bind_ip = 127.0.0.1
 
-# Specify port number (27017 by default...but typically 27018 for IIAB)
+# Specify port number (27017 by default).  Sugarizer Server & IIAB had earlier
+# used 27018.  https://docs.mongodb.com/manual/reference/default-mongodb-port/
 port = {{ mongodb_port }}
 
 # Fork server process (false by default)