AD, DNS, DHCP - Servers in, Clients in 10.10.49/24

I need to replace server and client IP addresses and still allow old IP addresses to reach the new IP address/host names.

Clients/Workstations be addressed 10.10.49/24 with the gateway (switch 8 is gateway)

Servers will be addressed 10.10.50/24 with gateway (switch 8) is gateway.

To configure domain controllers (two of them) on windows server 2008 with AD, DNS, DHCP:

1. I will keep existing IP address in tcp/ip4 properties but will add the new IP address through advanced TCP/IP settings...
   Set the IP address on domain controller to The current gateway is  Do I add as the additional new gateway? on Client workstations; would default gateway be or  

2. in DHCP, to configure the new DHCP Scope for workstations to contact dc1 and dc2 with the new IP address (dc2) and (dc2) to retrieve the an IP of the client subnet-
    Do I set the new scope "scope options" wiith:
             Router: the default gateway of the clients or servers
             DNS Servers: the domain controllers new IP:;
3. The "server options" in DHCP contains currently
       DNS Servers: old/current ip address of dc1 dc2
       DNS domain name: domainname.whatever
       NTP server: the time servers

Will the default gateway on domain controllers be of the severs subnet gateway (  If so,  will clients on the range and DHCP be configured as for the gateway or as the gateway?
Who is Participating?

Improve company productivity with a Business Account.Sign Up

I did not understand what you meant by "switch 8" but I will assume it is a router.

Default gateway = default route: The route to (anywhere)

Anything on : GW
Anything on : GW
To follow what baller119 says, this 'switch8'(lets say its a layer3 switch) - it should be doing the 'routing between different subnets' as well...

What models are these switches?
Don't assign multiple GW's to servers or clients...that is taken care of on the router/switch
NEW Internet Security Report Now Available!

WatchGuard’s Threat Lab is a group of dedicated threat researchers committed to helping you stay ahead of the bad guys by providing in-depth analysis of the top security threats to your network.  Check out this quarters report on the threats that shook the industry in Q4 2017.

Are you putting clients and servers on separate networks because you ran out of IP's on your network?
zfishAuthor Commented:
OK, so on the domain controller, could I configure the domain controllers with an IP address and gateway of the "server" subnet.. GW And in DHCP set it up to distribute to clients for default gateway while still allowing all communication flow to services on domain controllers?  

Yes it's a router rather than a switch.

The main reason I'm placing servers and workstations in a separate subnet but same subnet mask is to prevent broadcast traffic and its been requested by the customer for servers and clients to not be in the subnet.  Main purpose to get out of is because we will have multiple locations in the future and directed to do so by regional office.
@zfish your description of your IP setup makes sense. If your router is already configured correctly and you have the correct default gateways being provided to each node on each subnet then it should work as you expect.
zfishAuthor Commented:
When I added the IP address to the domain controllers it didn't add the secondary IP address to DNS.  Wherever there is a record containing existing DC IP should I add as well the a second record (reserve, a record, prt, cname, etc) for the new IP? dc1 and .5 for dc2?  

Is it ok for DNS to contain multiple IPs/records to a same host (host would be dc1 and dc2)?

I ask because in the DHCP scope, I added the new-secondary IP of DC1 and DC2; with router that the client computers would use which is When adding these IPs it displayed it couldn't locate in DNS to resolve.
At this point, you may be having issues with multiple IP's being assigned to the NIC on a DC. I suggest removing the old IPs completely and setting each DC/DNS/DHCP server to a single IP in the new range (,

You say in the original question you wish to "allow old IP's to reach the new IP address/hostnames" and having the old subnet on your servers is not going to accomplish any benefit.

So, for each DC, set one IP address and if DNS is hosted on the DC, put the same single IP in the primary DNS and leave secondary blank.

I can help with further questions if you need it.
zfishAuthor Commented:
If I remove the current IPs from the NIC of the domain controllers and use the new IP address range, the domain controllers then will be using with default gateway as while workstations and servers that have not yet transitioned to the new IP; won't they then not be able to communicate with DCs?
What is your transition plan? How long do you plan to keep others on the old IP? You should probably not have dual homed DC's. It is not recommended and can cause strange issues.
zfishAuthor Commented:
Transition time could be several months.

servers and domain controllers: new ip  [old is 192.168.101.x] in same vlan 13
workstations/printers new ip                   [Old is 192.168.101.x] in same vlan 13

If I do not have the domain controllers assigned with the new IP (10.10.50.x); how would I set DHCP to assign IPs 10.10.49.x to workstations.  
It is configured like the following but it doesn't distribute ips.  If I manually assign the ip I can ping the old IPs but it can't find the dns record.

Scope Options on dc1 (dc2 has no changes done to dhcp as of yet)
003 Router :
006 DNS Servers:; (currently these IPs are secondary-assigned to same nic of the 192.168.101.x
015 dns domain name:

For this scope, its set to dynamically update dns a and ptr records only
@zfish, my suggestion is to use your router to route traffic between subnets. DHCP will issue addresses in a subnet for which your router is setup, as long as you setup DHCP relay in the router. I also suggest that you set your new IPs for each server and do not setup more than one subnet per NIC. If some clients need to be on the old subnet 192.x then place them on their own subnet in the router.
zfishAuthor Commented:
how do I setup dhcp relay?  the switch is a 3560x
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.