System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP)

Verifying Basic Client/Server Communication

The best way to show that your client is talking to the LDAP server is with the ldaplist command. The simplest form, ldaplist with no arguments will dump all the containers on the server. This works as long as the containers exist, and do not have to be populated. If the first step works, you can try ldaplist passwd username or ldaplist hosts hostname but if they contain lots of data you might want to pick a less populated service, or pipe them to head or more.