DHCP block list RRS feed

  • Question

  • Good morning everyone,
    I got a notice in the DHCP logs, which are crowding my logs:

    DHCP services were denied to computer with hardware address 00-10-18-C5-0C-AD, hardware type 1 and FQDN / host name is not specified because it did not correspond to any entry in the list of permissions.

    I work with the DHCP whitelist, the message is clear, however, how do I identify which is the address that is being blocked?
    These logs appear every 5 seconds.

    Tuesday, June 4, 2013 11:59 AM


  • Those event log errors are Event ID 20096 - 20100.

    Assuming you have managed switches, you can log into the switch and identify the switch port# that MAC 00-10-18-C5-0C-AD is sitting on.

    However, you stated you are looking for what IP was denied? My assumption is if a DHCP client were to be denied an IP, then no IP would have been given the client. Unless I'm mistaking what you're asking?

    Ace Fekay
    MVP, MCT, MCITP/EA, MCTS Windows 2008/R2 & Exchange 2007, Exchange 2010 EA, MCSE & MCSA 2003/2000, MCSA Messaging 2003
    Microsoft Certified Trainer
    Microsoft MVP - Directory Services
    Technical Blogs & Videos: http://www.delawarecountycomputerconsulting.com/

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

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    • Proposed as answer by Meinolf Weber Tuesday, June 4, 2013 7:05 PM
    • Marked as answer by J.Carlos.Rib Thursday, June 6, 2013 4:55 PM
    Tuesday, June 4, 2013 3:17 PM