root@cabrini:/etc/samba# samba_upgradedns --dns-backend=BIND9_DLZ 
Reading domain information
DNS accounts already exist
No zone file /var/lib/samba/bind-dns/dns/MYFIRM.LAN.zone (normal)
DNS partitions already exist
Adding dns-cabrini account
check_spn_alias_collision: trying to add SPN 'DNS/cabrini.myfirm.lan' on 'CN=dns-cabrini,CN=Users,DC=myfirm,DC=lan' when 'host/cabrini.myfirm.lan' is on 'CN=CABRINI,OU=Domain Controllers,DC=myfirm,DC=lan'
See /var/lib/samba/bind-dns/named.conf for an example configuration include file for BIND
and /var/lib/samba/bind-dns/named.txt for further documentation required for secure DNS updates
Finished upgrading DNS