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    Reject or Block DHCP request

    Scheduled Pinned Locked Moved DHCP and DNS
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    • H
      hibrid0
      last edited by

      Hi, I have my network with pfSense and call the ISP to disable the DHCP on his modem, that's OK.
      But sometimes the ISP reactive the DHCP on his modem.

      I want to know how to block the dhcp traffic from my Lan to the ISP modem.

      My Network:

      LAN Users–>>ETH1 (192.168.100.0/24)PfSense -->ETH1(192.168.0.101 )-->>ISP Modem

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      • KOMK
        KOM
        last edited by

        How is it causing a problem?  If your WAN is set to static IP, it won't care if upstream can offer addresses, and your LAN won't ever see those offers anyway.

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        • JKnottJ
          JKnott
          last edited by

          I want to know how to block the dhcp traffic from my Lan to the ISP modem.

          ???

          If you have pfSense between your LAN and the modem, then what happens WRT DHCP on the WAN side shouldn't appear on the LAN.  Also, consider how DHCP works.  A client REQUESTS and a server provides an address.  Any DHCP request on your LAN will not make it past pfSense.  So, any device using DHCP on your LAN should get an address from pfSense and not the ISP.  The only exception is if you configured pfSense as a DHCP relay.

          Bottom line, it's unlikely you're seeing DHCP addresses from your ISP on your LAN.  Why do you think that's happening?

          PfSense running on Qotom mini PC
          i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
          UniFi AC-Lite access point

          I haven't lost my mind. It's around here...somewhere...

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