oh, you're trying to point a web application at the Gluu Server LDAP? Yes, you'll have to make sure that port tcp/1636 is open. Also, its a bad practice to give out the "cn=directory manager" password to any applications. Normally I'd create an ou under cn=config (like ou=applications,cn=config) and add a entry for each application. Then you'd have to create an ACI, giving that entry access to the data it needs (for example, probably just add an aci to ou=people,o=<org-inum>,o=gluu. For more info on ACI's see the [OpenDJ Admin Guide Chapter 6](http://opendj.forgerock.org/opendj-server/doc/bootstrap/admin-guide/#chap-privileges-acis) Directory Manager has too much write permissions--in fact aci's are not even evaluated, so it should only be used by the a privileged user for ad hoc queries or administration.
Also, make sure you use LDAPS...
But net, net... LDAP is a terrible applicaiton interface. You're limited to password authentication, and it requires a tight bundling between the application and the LDAP server. Can't you update the application to use OpenID Connect? Our new oxd software makes that really easy if you're using php or python...