locked
Win2k8 R2 DHCP problem with Option82 RRS feed

  • Question

  • I have changed from ISC DHCP to Win2k8R2 DHCP cluster (lastest update on Feb, 2012), providing IP for IPTV network.
    I have encoutered a problem : after changing from ISC DHCP to MS DHCP, many clients cannot get IP.

    Topology : client --> dslam (option82 enabled) --> router (as dhcp relay) --> DHCP cluster

    After troubleshooting, the reason is : DHCP Discover is inserted with Option82, the ISC returns DHCP Offer with original option82 inside, but MS DHCP returns DHCP Offer without Option82. This cause the dslam drop packet.

    The dslam drop packet is Zyxel. If option82 is disabled, users can get IP OK. Another dslam - from Huawei - does not drop that packet. Its users can get IP OK.

    I tried to set predefined option82 to MS DHCP but server cannot include option82 in Offer messages.

    Does anyone know how to fix this ? Or how to report problem to Microsoft ?

    Tuesday, February 28, 2012 10:57 AM

Answers

  • See if the following help. I also offered a "what is it" link for others that my be following this thread.

    .

    What is DHCP Option 82?
    Quoted: "To put it simply, DHCP Option 82 is the "DHCP Relay Agent Information Option. Wasn't that easy? Option 82 was designed to allow a DHCP Relay Agent to insert circuit specific information into a request that is being forwarded to a DHCP server. Specifically the option works by setting two sub-options: Circuit ID and Remote ID."
    http://slaptijack.com/networking/what-is-dhcp-option-82/

    There are no known issues around option 82. If your dhcp client honors this option, definining it at Microsoft DHCP Server side should work for you.
    http://social.technet.microsoft.com/Forums/en-US/winserverNIS/thread/0675017f-932e-4f59-8f02-6c5ea1c5baa3

    More info:

    Microsoft Windows DHCP Team Blog: Option 082:
    You will need to use a "DHCP Server Callout API" to make this work:
    Quoted: "Below is a sample callout code which enables option 82 support with Microsoft DHCP Server. DHCP option 82 is “DHCP Relay Agent Information Option” and allows a DHCP Relay Agent to insert circuit specific information into a request that is being forwarded to a DHCP Server.
    Microsoft DHCP Server currently drops option 82 in the response packets. This callout DLL stores option 82 inside packet context in DhcpNewPktHook and then adds the option back in the DhcpPktSendHook using the information stored in packet context."
    http://blogs.technet.com/b/teamdhcp/archive/2009/07/06/dhcp-server-callout-api-usage.aspx

    Microsoft Windows DHCP Team Blog - search any DHCP topic:
    http://blogs.technet.com/teamdhcp/archive/2005/09/21/411344.aspx


    Ace Fekay
    MVP, MCT, MCITP Enterprise Administrator, MCTS Windows 2008 & Exchange 2007 & Exchange 2010, Exchange 2010 Enterprise Administrator, MCSE & MCSA 2003/2000, MCSA Messaging 2003
    Microsoft Certified Trainer
    Microsoft MVP - Directory Services
    Complete List of Technical Blogs: http://www.delawarecountycomputerconsulting.com/technicalblogs.php

    This posting is provided AS-IS with no warranties or guarantees and confers no rights.

    FaceBook Twitter LinkedIn

    • Marked as answer by Nguyên Diệp Wednesday, February 29, 2012 2:39 AM
    Tuesday, February 28, 2012 11:15 PM
  • Microsoft DHCP Server currently drops option 82 in the response packets. This callout DLL stores option 82 inside packet context in DhcpNewPktHook and then adds the option back in the DhcpPktSendHook using the information stored in packet context."
    http://blogs.technet.com/b/teamdhcp/archive/2009/07/06/dhcp-server-callout-api-usage.aspx

    Thanks, that's what I am looking for !
    Wednesday, February 29, 2012 2:41 AM

All replies

  • See if the following help. I also offered a "what is it" link for others that my be following this thread.

    .

    What is DHCP Option 82?
    Quoted: "To put it simply, DHCP Option 82 is the "DHCP Relay Agent Information Option. Wasn't that easy? Option 82 was designed to allow a DHCP Relay Agent to insert circuit specific information into a request that is being forwarded to a DHCP server. Specifically the option works by setting two sub-options: Circuit ID and Remote ID."
    http://slaptijack.com/networking/what-is-dhcp-option-82/

    There are no known issues around option 82. If your dhcp client honors this option, definining it at Microsoft DHCP Server side should work for you.
    http://social.technet.microsoft.com/Forums/en-US/winserverNIS/thread/0675017f-932e-4f59-8f02-6c5ea1c5baa3

    More info:

    Microsoft Windows DHCP Team Blog: Option 082:
    You will need to use a "DHCP Server Callout API" to make this work:
    Quoted: "Below is a sample callout code which enables option 82 support with Microsoft DHCP Server. DHCP option 82 is “DHCP Relay Agent Information Option” and allows a DHCP Relay Agent to insert circuit specific information into a request that is being forwarded to a DHCP Server.
    Microsoft DHCP Server currently drops option 82 in the response packets. This callout DLL stores option 82 inside packet context in DhcpNewPktHook and then adds the option back in the DhcpPktSendHook using the information stored in packet context."
    http://blogs.technet.com/b/teamdhcp/archive/2009/07/06/dhcp-server-callout-api-usage.aspx

    Microsoft Windows DHCP Team Blog - search any DHCP topic:
    http://blogs.technet.com/teamdhcp/archive/2005/09/21/411344.aspx


    Ace Fekay
    MVP, MCT, MCITP Enterprise Administrator, MCTS Windows 2008 & Exchange 2007 & Exchange 2010, Exchange 2010 Enterprise Administrator, MCSE & MCSA 2003/2000, MCSA Messaging 2003
    Microsoft Certified Trainer
    Microsoft MVP - Directory Services
    Complete List of Technical Blogs: http://www.delawarecountycomputerconsulting.com/technicalblogs.php

    This posting is provided AS-IS with no warranties or guarantees and confers no rights.

    FaceBook Twitter LinkedIn

    • Marked as answer by Nguyên Diệp Wednesday, February 29, 2012 2:39 AM
    Tuesday, February 28, 2012 11:15 PM
  • Microsoft DHCP Server currently drops option 82 in the response packets. This callout DLL stores option 82 inside packet context in DhcpNewPktHook and then adds the option back in the DhcpPktSendHook using the information stored in packet context."
    http://blogs.technet.com/b/teamdhcp/archive/2009/07/06/dhcp-server-callout-api-usage.aspx

    Thanks, that's what I am looking for !
    Wednesday, February 29, 2012 2:41 AM