none
merging two dhcp servers RRS feed

  • Question

  • Windows Server 2008 R2

    i have two DHCP servers installed on domain controllers. DHCP1 have address pool from 192.168.1.1 to 192.168.1.150 while DHCP2 address pool is from 192.168.1.151 to 192.168.1.254

    i exported both DHCP config using "netsh dhcp server export c:\somefile.txt all" resulting in two separate files.

    now i configures a test DHCP server, imported the config using "netsh dhcp server import c:\somefile.txt all". it works for the first file(DHCP1). but when i try to import the config from the second file (DHCP2), it tells me:

    Error while importing subnet 192.168.1.0 "Data1"

    This subnet already exists on the local server. An internal error occured.

    i'm doing this in preparation for a DR scenario where i only have a single server for DNS and DHCP.

    is there any other way to merge this two address pool?

    Wednesday, December 21, 2016 11:45 AM

Answers

  • 192.168.1.0 IS the same subnet for both scopes
    • Edited by fancypants1975 Wednesday, December 21, 2016 11:11 PM
    • Marked as answer by Reno Mardo Thursday, December 22, 2016 8:30 AM
    Wednesday, December 21, 2016 3:27 PM
  • Hi Mardo,

    >>is there any other way to merge this two address pool?

    I am afraid that there has no other ways of that merge two address pools that are both in the same subnet or network ID.

    Best Regards

    John


    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.


    • Edited by John Lii Thursday, December 22, 2016 5:56 AM
    • Marked as answer by Reno Mardo Thursday, December 22, 2016 8:30 AM
    Thursday, December 22, 2016 5:56 AM

All replies

  • 192.168.1.0 IS the same subnet for both scopes
    • Edited by fancypants1975 Wednesday, December 21, 2016 11:11 PM
    • Marked as answer by Reno Mardo Thursday, December 22, 2016 8:30 AM
    Wednesday, December 21, 2016 3:27 PM
  • i know. maybe i should rephrase.

    in a DR scenario, how would you continue serving IP address requests should the primary data center goes offline? the primary data center is using split-scope and only one server (DC with DNS) is available in the DR site.

    Thursday, December 22, 2016 5:08 AM
  • Hi Mardo,

    >>is there any other way to merge this two address pool?

    I am afraid that there has no other ways of that merge two address pools that are both in the same subnet or network ID.

    Best Regards

    John


    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.


    • Edited by John Lii Thursday, December 22, 2016 5:56 AM
    • Marked as answer by Reno Mardo Thursday, December 22, 2016 8:30 AM
    Thursday, December 22, 2016 5:56 AM
  • Sorry I cannot offer a solution but question why in DR would assigning IP addresses be a concern unless you have leases set in hours rather than say 30 days?  DHCP keeps the lease and tries to renew at half intervals, 15 days, 7 days, 3.5 days etc so unless you were in DR for 30 days it should never really be an issue?
    Thursday, December 22, 2016 8:16 AM
  • issue is with leases that are expiring/have expired how to accommodate them when in a DR scenario?

    since i have a 3rd DNS server in the DR site, why not have the same for DHCP? just to cover all the bases.

    at this point it seems Microsoft has left this critical piece of the infrastructure to languish. we have DAG/clustering for Exchange and file servers for redundancy but not so much with DHCP. even in 2012 R2, a maximum of two DHCP servers is all one can have.

    ok i'm ranting here. thanks for the replies.

    Thursday, December 22, 2016 8:28 AM
  • hi,

    now i know. feature request: built-in redundancy for failover/switchover for DHCP servers like DNS servers.

    Thursday, December 22, 2016 8:30 AM
  • Hi Reno,

    I am glad to hear that your issue was successfully resolved.

    If there is anything else we can do for you, please feel free to post in the forum.

    Best Regards

    John


    Please remember to mark the replies as answers if they help.
    If you have feedback for TechNet Subscriber Support, contact tnmff@microsoft.com.

    Friday, December 23, 2016 2:11 AM
  • You will probably need to manually edit the two files into one that doesn't contain any duplicate information and import that. 

    Friday, December 23, 2016 3:18 AM