Hello and welcome to LinuxQuestions,
You cannot migrate Active Directory to OpenLDAP one to one. You'll have to make a decision on what you want to migrate, for example users and take it from there. You might be interested in
389 Directory Server or
Calculate Directory Server. Apart from that, don't expect LQ users to provide step by step guides, lots of them can be found on the internet. When you encounter problems following a howto, that's when you turn to LQ for answers.
Looking forward to your participation in the forums. Have fun with Linux.
Kind regards,
Eric
