LDAP (ad) AND LOCAL AUTHENTIFICATION ON OTRS 3.2.2

[Sousou]

I contact you actually in order to have your adivces and solution because we are using on our differents sites the ticketing tool otrs.
we have 5 sites, on one site the authentification is made via active directory. (ldap) for the other sites we need to made it active directory connectable
at this time i read the technical review and i understood that i have to make 2 adaptations :
- one in the config file where i have to indicated the domain controller, the username as identificator etc
-second adaptation is to do it directly in the parametres into otrs and indicated the ldap username for each users

but the issue and my question is for some people using otrs they are not recognized all in our active directory

so can you tell me how and if they exist a way to allow on otrs portal two kind of authentification ( so active directory and the native one)?

Can you send me what i have to indicated in the config file to have those two authentification methodes available?

when all those adaptation is made, do I have to restart a specific pool or services on the windows server?
please indicate me please how to make those adaptation ?
ps: is it needed to created an OU in AD with all the people who are granted to access on otrs? ( authentification right will be managed by a gpo or not only on the parameters into otrs portal?)

thank you community otrs