[Samba] samba 4.5.12 -- drs showrepl only 3 DCs?

[lingpanda101]

On 7/18/2017 2:08 PM, C.Kindler via samba wrote:
> Hello,
>
> updated from samba-4.4.14 to samba-4.5.12 the output from one DC
> "samba-tool drs showrepl" does not show all 4 DC:
> @DC02: no outbound  and inbound neigbour to DC04
> @DC04: no outbound  and inbound neigbour to DC02
> @DC01 and DC03 are shown all 3 neigbours:
>
> - How to fix it?
> I tried manually replicate, but this works only for some minutes... Luckily
> the login part is working...
>
>
>
> --
> output from @DC2:
> ==== KCC CONNECTION OBJECTS ====
>
> Connection --
>          Connection name: 981ad8a8-9549-4013-a467-5fe3b52b5f0e
>          Enabled        : TRUE
>          Server DNS name : DC01.ad.mydomain.net
>          Server DN name  : CN=NTDS
> Settings,CN=DC1,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=ad,DC=mydomain,DC=net
>                  TransportType: RPC
>                  options: 0x00000001
> Warning: No NC replicated for Connection!
> Connection --
>          Connection name: ea5261d8-67e4-497c-aa7c-118da0b95791
>          Enabled        : TRUE
>          Server DNS name : DC03.ad.mydomain.net
>          Server DN name  : CN=NTDS
> Settings,CN=DC03,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=ad,DC=mydomain,DC=net
>                  TransportType: RPC
>                  options: 0x00000001
> Warning: No NC replicated for Connection!
>
>
>
> output from  DC01
> ==== KCC CONNECTION OBJECTS ====
>
> Connection --
>          Connection name: 1a500d9c-6035-4c4f-90ca-7a2e4517850f
>          Enabled        : TRUE
>          Server DNS name : DC03.ad.wuestenrot.at
>          Server DN name  : CN=NTDS
> Settings,CN=DC03,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=ad,DC=mydomain,DC=net
>                  TransportType: RPC
>                  options: 0x00000001
> Warning: No NC replicated for Connection!
> Connection --
>          Connection name: 1d7ab798-0ee9-4735-af58-ecbd450ade14
>          Enabled        : TRUE
>          Server DNS name : DC02.ad.mydomain.net
>          Server DN name  : CN=NTDS
> Settings,CN=DC02,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=ad,DC=mydomain,DC=net
>                  TransportType: RPC
>                  options: 0x00000001
> Warning: No NC replicated for Connection!
> Connection --
>          Connection name: 8496b819-e395-49a7-854b-78ed80ec58f6
>          Enabled        : TRUE
>          Server DNS name : DC04.ad.mydomain.net
>          Server DN name  : CN=NTDS
> Settings,CN=DC04,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=ad,DC=mydomain,DC=net
>                  TransportType: RPC
>                  options: 0x00000001
> Warning: No NC replicated for Connection!

This may be perfectly fine depending on how you have sites and services 
set up. The KCC was updated beginning in 4.5.0

KCC improvements for sparse network replication
-----------------------------------------------

The Samba KCC will now be the default knowledge consistency checker in
Samba AD. Instead of using full mesh replication between every DC, the
KCC will set up connections to optimize replication latency and cost
(using site links to calculate the routes). This change should allow
larger domains to function significantly better in terms of replication
traffic and the time spent performing DRS replication.

-- 
--
James