I have OWA logon page for Exchange 2016 on F5 APM version 13.1.3
i have created LDAP authentication pool server
I want to add the ability for my APM profile to use UPN as well as SamAccountname.
Note : the AD domain is different to the UPN domaine.
what is the best way to do this ?
By default, AD will look for / verify the UPN or SamAccountName.
It is hard to answer your question, due to other unknowns that could cause issues, even if you have APM correctly configured.
See the below configuration guide that may help.