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Multiple DHCP servers RRS feed

  • Question

  • We have a W2KR2 domain infra with 3 DC's and 500 Windows 7 Thick clients

    For almost 10 years we had a flat network infrastructure, 10.128.0.0/16 subnet.

    We are going to create multilple Vlan's now with the help of a network engineer, and migrate our desktop environment to VDI's.

    I'm going to install and configure a new W2K12R2 DHCP server with the new vlan's scopes and settings

    Can the current W2K8R2 DCHP server with the 10.128.0.0/16 scope stay active for the time being?

    Other question

    If I install/configure a second W2K12R2 DHCP server in Hot Standby Mode, can I configure de second DHCP server to be the only server to manage the 10.128.0.0/16 subnet. Or is is not possible because it's in standby mode?

    If so, should I then consider load balance mode??

    Thanks

    Wednesday, May 11, 2016 10:23 AM

Answers

  • Hi Biga_b,

    >>If we migrated our desktop environment to VDI, we will not be using the 10.128.0.0/16 subnet anymore for clients and printers. Only for our servers, but those are static ip addresses offcourse

    As stated, if you moved the clients and printers to the new DHCP environment, does the old DHCP server exists make any sense? (the old servers have static IP address)

    You could use the new server 2012R2 to distribute IP addresses for these DHCP clients.

    If necessary, you could use DHCP relay agent for different subnet clients.

    DHCP relay agent

    https://technet.microsoft.com/en-sg/library/cc779610(v=ws.10).aspx

    Best regards,


    Andy_Pan

    • Marked as answer by Biga_b Thursday, May 12, 2016 12:03 PM
    Thursday, May 12, 2016 8:29 AM

All replies

  • Hi

    Can the current W2K8R2 DCHP server with the 10.128.0.0/16 scope stay active for the time being? >>> If you don't change ip helper address on switches&routers clients still use old dhcp server.But personally i never prefer multiple dhcp server on domain for same subnets,also considering ip helper there are potential problems can be.I recommend that just migrate dhcp from old to new clsuter servers,thats the best practice.

    If need check this for migration ; https://blogs.technet.microsoft.com/canitpro/2013/04/28/step-by-step-migration-of-dhcp-from-windows-server-2003-to-windows-server-2012/

    then check this for dhcp failover cluster setup ; https://technet.microsoft.com/en-us/library/hh831385(v=ws.11).aspx


    This posting is provided AS IS with no warranties or guarantees,and confers no rights. Best regards Burak Uğur

    Wednesday, May 11, 2016 10:38 AM
  • Biga,

    2 DHCP server working at the same time is not possible on the same subnet.

    Check the DHCP lease time also while going on to the cluster server.


    Thanks,

    Prasad S

    Wednesday, May 11, 2016 10:45 AM
  • Have a look at this. You can do almost anything with failover.

    https://technet.microsoft.com/en-us/library/dn338986(v=ws.11).aspx

    Wednesday, May 11, 2016 11:16 AM
  • The new W2K12R2 DHCP is going to be installed on a diffrent subnet 10.156.220.0/23. The new vlan's/scopes will be configured on this server. This DHCP server will not manage our current 10.128.0.0./16 scope.

    If we migrated our desktop environment to VDI, we will not be using the 10.128.0.0/16 subnet anymore for clients and printers. Only for our servers, but those are static ip addresses offcourse

    But forgot about the ip helpers. I suppose these need to be changed. Also for PXE. will talk to our network engineer

    Thanks

    Wednesday, May 11, 2016 11:28 AM
  • you can use old dhcp server,during the new dhcp server configuration.already mentioned do not change ip helper addrresses on swcitches&rourers,when the new dhcp server configuration complete then will change ip helpers to point new dhcp server....(so you will configure diffrent subnet)

    This posting is provided AS IS with no warranties or guarantees,and confers no rights. Best regards Burak Uğur

    Wednesday, May 11, 2016 11:53 AM
  • Hi Biga_b,

    >>If we migrated our desktop environment to VDI, we will not be using the 10.128.0.0/16 subnet anymore for clients and printers. Only for our servers, but those are static ip addresses offcourse

    As stated, if you moved the clients and printers to the new DHCP environment, does the old DHCP server exists make any sense? (the old servers have static IP address)

    You could use the new server 2012R2 to distribute IP addresses for these DHCP clients.

    If necessary, you could use DHCP relay agent for different subnet clients.

    DHCP relay agent

    https://technet.microsoft.com/en-sg/library/cc779610(v=ws.10).aspx

    Best regards,


    Andy_Pan

    • Marked as answer by Biga_b Thursday, May 12, 2016 12:03 PM
    Thursday, May 12, 2016 8:29 AM
  • Eventually we will remove the old DHCP server. But that will be one of the last step in this "migration"
    Thursday, May 12, 2016 12:07 PM