Remote authentication is one of those things that once set up correctly just work. We do not notice it, we simply put in our credentials and use it.

It takes some understanding and a tiny bit of thinking ahead when mapping AOS roles and permissions to LDAP/AD users and user groups.

So where to start?

First, follow Prism Element Security Guide: Configuring Authentication to set up remote authentication.
Run NCC Health Check: ldap_config_check.
For any issues leverage KBs:
KB-2066 Unable to Log In to the Prism web console using Group LDAP authentication
KB-3363 Prism: Troubleshooting LDAP Issues for Prism Log On
 

For those of you PowerShell fans there is a little bit of CLI available:
PowerShell Cmdlets Reference: LDAPConnection
PowerShell Cmdlets Reference: Domain