Using ldapsearch from the command line, it is possible to find all of the naming contexts of the directory server (lowest level distinguished names like o=tech-recipes).
The simplest version of this command (running ldapsearch locally on the LDAP server itself):
ldapsearch -s base -b "" objectclass=top
The resulting text will display the naming contexts, one per line, prefixed by namingcontext:
If you are running ldapsearch on a remote system, you can specify the directory server host (say, dir-serv) by adding
-h dir-serv
before the objectclass=top argument.