What's the easy way to do this?
yum list installed
will show you if it's installed.
will show you if the service is running (might be called slapd)
Config will be somewhere like /etc/openldap/* and you can see if it's been configured.
Test it by querying it with something like:
ldapsearch -x -b 'dc=mycompany,dc=com' 'objectclass=*'
but you might have to know how it's (supposed to be) configured to know what to search for.
Another way would be:
If this results in an integer (the PID of the process), you have a running OpenLDAP server. If there is no output, it's not running.