[Samba] Adding and removing users from groups - where is the audit trail?

[Mario Durate]

Folks, 

I am fairly new to Samba 4 so excuse my lame question.  Am trying to find
out where and how we can log account management activities on Samba 4.  For
example, domain admin adds an account to the domain admin groups or domain
admin disables an account due to employment separation.  I can¹t find any
record of this activity on any logs.  Am I missing something?

Thanks.