https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923042#M170432 Turn on DHCP snooping in your network. Thu, 12 Sep 2019 06:59:23 GMT Leo Laohoo 2019-09-12T06:59:23Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922919#M170429 <P>I have some LWAPPs running off of a Cisco WLC. How can I prevent someone from running a rogue DHCP server off the WLAN and causing an outage for Wi-Fi clients?</P> Mon, 05 Jul 2021 17:59:31 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922919#M170429 Sam Brynes 2021-07-05T17:59:31Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922927#M170430 <P>&nbsp;dhcp snooping config is the remediation for you.</P> Thu, 12 Sep 2019 00:41:06 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922927#M170430 balaji.bandi 2019-09-12T00:41:06Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922928#M170431 <P>Hi Balaji,</P><P>Where would I configure that on the WLC?</P><P>&nbsp;</P><P>Sam</P> Thu, 12 Sep 2019 00:47:50 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3922928#M170431 Sam Brynes 2019-09-12T00:47:50Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923042#M170432 Turn on DHCP snooping in your network. Thu, 12 Sep 2019 06:59:23 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923042#M170432 Leo Laohoo 2019-09-12T06:59:23Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923347#M170433 Configure the DHCP server on the virtual-interface. I think if you do that, the WLC will automatically forward the DHCP packets to only that one IP address. The rogue DHCP should not even hear the DHCP Request that way. I haven't tested it though :) Thu, 12 Sep 2019 15:11:46 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923347#M170433 patoberli 2019-09-12T15:11:46Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923517#M170434 <P>DHCP Snooping is the solution &amp; here how you can implement it</P> <P><A href="https://mrncciew.com/2012/12/27/understanding-dhcp-snooping/" target="_self">https://mrncciew.com/2012/12/27/understanding-dhcp-snooping/</A></P> <P>&nbsp;</P> <P>HTH</P> <P>Rasika</P> <P>*** Pls rate all useful responses ***</P> Thu, 12 Sep 2019 19:34:16 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923517#M170434 Rasika Nayanajith 2019-09-12T19:34:16Z https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923705#M170435 <P>Is DHCP snooping in the case of Wireless really needed?</P> <P>I mean, the WLC doesn't forward broadcasts by default and thus a rogue DHCP server on WLAN shouldn't cause any issues (unless the not recommended broadcast forwarding was enabled). Or did I miss something here?</P> Fri, 13 Sep 2019 05:58:55 GMT https://community.cisco.com/t5/wireless/cisco-wlc-wi-fi-network-how-to-prevent-someone-running-a/m-p/3923705#M170435 patoberli 2019-09-13T05:58:55Z