[Samba] DCs in multiple VLANs

[Stefan G. Weichinger]

I have 2 DCs at a customer that also run ISC-Kea-DHCP servers.

To be able to provide DHCP-Leases I added virtual interfaces to the 
servers with IPs in each VLAN.

In turn there also exist routes to the VLANs:

# ip r
default via 10.0.0.254 dev enp0s31f6 onlink
10.0.0.0/24 dev enp0s31f6 proto kernel scope link src 10.0.0.230
10.100.40.0/24 dev enp0s31f6.200 proto kernel scope link src 10.100.40.230
192.168.101.0/24 dev enp0s31f6.101 proto kernel scope link src 
192.168.101.230
192.168.102.0/24 dev enp0s31f6.102 proto kernel scope link src 
192.168.102.230
192.168.103.0/24 dev enp0s31f6.103 proto kernel scope link src 
192.168.103.230

In smb.conf I did this:

bind interfaces only = yes
interfaces = lo enp0s31f6

to only run the DC in the LAN network.

Otherwise there were 4 or 5 DNS-entries created for the hostname of the 
DC, which seemed problematic to me. Maybe it is not?

What if a client in LAN gets a DNS reply with a IP in the VLANs? timeouts?

-

To reply to DHCP-clients in the VLANs I need the specific interfaces + 
routes.

But if a client in a VLAN tries to "gpupdate" things fail: asymmetric 
routing, the replies don't get to the client.

I am not sure how to solve this.

Allow the DC to run on all interfaces?

And no, we don't have additional hardware to move the DHCP-services to.