[Samba] Samba4 AD with bind DNS / TKEY is unacceptable
Solved that by chowing the file used on /etc/bind/named.conf.options >>
tkey-gssapi-keytab "/var/lib/samba/private/dns.keytab";
chown bind.root /var/lib/samba/private/dns.keytab
I am using debian.