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Domain Controller with multiple network interfaces

%3CLINGO-SUB%20id%3D%22lingo-sub-2518948%22%20slang%3D%22en-US%22%3EDomain%20Controller%20with%20multiple%20network%20interfaces%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2518948%22%20slang%3D%22en-US%22%3E%3CP%3EI%20have%20two%20DCs%20which%20have%20network%20interfaces%20on%20two%20or%20three%20different%20VLANs.%20I%20only%20need%20a%20response%20on%20the%20corporate%20LAN%2C%20but%20the%20other%20VLAN%20is%20for%20VOIP%20and%20one%20server%20has%20a%20third%20network%20for%20VLANed%20traffic%20that%20doesn't%20touch%20the%20corporate%20LAN%20but%20still%20goes%20out%20to%20the%20internet.%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3EIn%20networking%20I%20have%20selected%20the%20tick-box%20for%20'register%20this%20connection's%20address%20in%20DNS%20'%20for%20only%20the%20network%20interface%20on%20the%20corporate%20LAN.%20However%20DNS%20is%20getting%20all%20the%20two%20(or%20three)%20addresses%20and%20ping%20is%20failing%20because%20it%20is%20resolving%20the%20address%20to%20an%20IP%20address%20that%20I%20don't%20expect%20to%20respond%20on%20that%20VLAN.%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3EWhy%20is%20this%20happening%20and%20how%20can%20I%20resolve%20it%3F%20This%20is%20Windows%202016%20Server%2C%20by%20the%20way.%3C%2FP%3E%3CP%3E%26nbsp%3B%3C%2FP%3E%3CP%3ETim%3C%2FP%3E%3C%2FLINGO-BODY%3E%3CLINGO-LABS%20id%3D%22lingo-labs-2518948%22%20slang%3D%22en-US%22%3E%3CLINGO-LABEL%3ENetworking%3C%2FLINGO-LABEL%3E%3CLINGO-LABEL%3EWindows%20Server%3C%2FLINGO-LABEL%3E%3C%2FLINGO-LABS%3E%3CLINGO-SUB%20id%3D%22lingo-sub-2519166%22%20slang%3D%22en-US%22%3ERe%3A%20Domain%20Controller%20with%20multiple%20network%20interfaces%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2519166%22%20slang%3D%22en-US%22%3E%3CP%3EMulti-homing%20a%20domain%20controller%20will%20always%20cause%20no%20end%20to%20grief%20for%20active%20directory%20domain%20DNS.%20Better%20option%20is%20to%20install%20the%20viop%20software%20on%20another%20instance%20of%20windows.%3C%2FP%3E%0A%3CP%3E%26nbsp%3B%3C%2FP%3E%0A%3CP%3E%26nbsp%3B%3C%2FP%3E%3C%2FLINGO-BODY%3E%3CLINGO-SUB%20id%3D%22lingo-sub-2519170%22%20slang%3D%22en-US%22%3ERe%3A%20Domain%20Controller%20with%20multiple%20network%20interfaces%3C%2FLINGO-SUB%3E%3CLINGO-BODY%20id%3D%22lingo-body-2519170%22%20slang%3D%22en-US%22%3EThank%20you...%20The%20other%20networks%20are%20on%20the%20DC%20because%20it's%20also%20doing%20DHCP.%20Should%20I%20have%20a%20separate%20DHCP%20server%20in%20the%20VOIP%20VLAN%20to%20provide%20addressing%20to%20the%20phones%3F%3C%2FLINGO-BODY%3E
Occasional Contributor

I have two DCs which have network interfaces on two or three different VLANs. I only need a response on the corporate LAN, but the other VLAN is for VOIP and one server has a third network for VLANed traffic that doesn't touch the corporate LAN but still goes out to the internet.

 

In networking I have selected the tick-box for 'register this connection's address in DNS ' for only the network interface on the corporate LAN. However DNS is getting all the two (or three) addresses and ping is failing because it is resolving the address to an IP address that I don't expect to respond on that VLAN.

 

Why is this happening and how can I resolve it? This is Windows 2016 Server, by the way.

 

Tim

7 Replies

Multi-homing a domain controller will always cause no end to grief for active directory domain DNS. Better option is to install the viop software on another instance of windows.

 

 

Thank you... The other networks are on the DC because it's also doing DHCP. Should I have a separate DHCP server in the VOIP VLAN to provide addressing to the phones?

Better option is to use layer 3 routing hardware for this purpose. If you must do it on windows then use another member server for this role.

 

 

 

Thanks. We have L3 switches so I'm not sure what has been done. Can you refer me to any best practice?

Your router should have a dhcp relay agent option.

Support multiple subnets with one DHCP server by configuring DHCP relay agents | Microsoft Docs

DHCP Subnet Selection Options | Microsoft Docs

 

(please don't forget to mark helpful replies)

 

 

To be clear the phone system is running on a different server.
best response confirmed by TimGowen (Occasional Contributor)
Solution

Sounds good, just don't multi-home your domain controllers.

 

(please don't forget to mark helpful replies)