Changing DNS domain/SOA values with samba-tool?

[Adam Tauno Williams]

Okay, I can change the IP of the host entry for the DC.

samba-tool dns update 127.0.0.1 micore.us barbel A 172.16.0.128
192.168.5.2

Works great.

But how can I change the value of the root "." entry of the domain.
Thatalso holds an A record I don't seem to be able to change.

samba-tool dns query 127.0.0.1 micore.us @ ALL
Password for [administrator at MICORE.US]: **************8
  Name=, Records=3, Children=0
    SOA: serial=5, refresh=900, retry=600, expire=86400,
ns=barbel.micore.us., email=hostmaster.micore.us. (flags=600000f0,
serial=5, ttl=3600)
    NS: barbel.micore.us. (flags=600000f0, serial=1, ttl=900)
*** A: 192.168.231.132 (flags=600000f0, serial=1, ttl=900) *****
  Name=_msdcs, Records=0, Children=0
  Name=_sites, Records=0, Children=1
  Name=_tcp, Records=0, Children=4
  Name=_udp, Records=0, Children=2
  Name=barbel, Records=1, Children=0
    A: 192.168.5.2 (flags=f0, serial=3, ttl=900)
  Name=DomainDnsZones, Records=0, Children=2
  Name=ForestDnsZones, Records=0, Children=2

But what is the value for <name> in "samba-tool dns update 127.0.0.1
micore.us <name> A 192.168.231.132 192.168.5.2" in order to modify that
entry.  I've tried "", ".", "@"....  none of which map to a record in
the LDB, thus yielding -

ERROR(runtime): uncaught exception - (9701,
'WERR_DNS_ERROR_RECORD_DOES_NOT_EXIST')