Hello, I have win2k3 single root domain with one winDC and one centos 6.4 samba 4.0.7 with internal DNS successfuly (asI thought) joined in. When both Dcs online everything works fine, but I'm confused with DNS zone replication. both dcs have record DC=mydomain.local,CN=MicrosoftDNS,dc=DomainDnsZones,dc=mydomain,dc=local with identical GUID an identical SOA record pointing to winDC as primary server same staff for DC=_msdcs.mydomain.local,CN=MicrosoftDNS,dc=ForestDnsZones,dc=mydomain,dc=local as far as i know in proper envirement for w2k3 GUID of this records should be different on DCs as well as SOA records for win2008 domains i can see zones in cn=MicrosoftDNS,cn=system,dc=mydomain,dc=local My questions is: 1) Where exactly samba stores dns zones and how it behaves it? 2) Can i safely demote winDC from domain and than change SOA primary server record to sambaDC, how it will affect on a next winDC joined to domain? 3) Contents of this zones doesn't bother me, as far as i know DC will create all srv records on reboot and workstation will create host record with ipconfig /registerdns all other records in zones are junk, is there a way to start a new life with a "clean" dns zones? 4) Will upagrade of samba solve this issue? Thank you for your consideration.