[Samba] Error joining Samba 4.7.4 DC to existing Win2008R2 domain

[Claudio Nicora]

> Check the DNS settings for the sambom.Local zone where it is located ForestDnsZone or DomainDnsZone.
> Must be in DomainDnsZone
>
> also it is necessary to make sure that in ForestDnsZone there is a zone _msdcs.sambom.local
Both ForestDnsZone and DomainDnsZone only contain "_sites" and "_tcp" 
domains, no "_msdcs".
Tried to create "_msdcs" zones manually but got the same failure in 
samba-tool join.

Claudio