Our client connects to an untrusted port; all ports are untrusted by default. When the client machine sends a DHCPDISCOVER message with DHCP Snooping enabled, the switch will only send the DHCP broadcast message to trusted ports. In this case our distribution switch is acting as the DHCP serve...
Since the client sends theDHCPDISCOVERmessage to the local broadcast address, if a DHCP server is configured on the local network, it will also receive the message. If multiple DHCP servers are configured on the local network, they all will receive theDHCPDISCOVERmessage. If multiple DHCP server...
In such a situation, you need to configure the router's interface connected to the DHCP server as a DHCP relay agent. To configure a router's interface as a DHCP relay agent, use the following command in interface configuration mode. Router(config-if)#ip helper-address [ip-address-of-the...
Step 2:Configure the trusted ports. These are ports that are trusted and are allowed to send ARP packets. This can be done using the command “ip arp inspection trust <interface>” Step 3:Configure the DHCP snooping database. This is used to build the DAI database. This can be done us...
In this post, a term DHCP Snooping will be introduced to help users to avoid illegal IP addresses. What Is DHCP Snooping? DHCP Snooping is a layer 2 security technology incorporated into the operating system of a capable network switch that drops DHCP traffic determined to be unacceptable. ...
Configure the DHCP function on the router to deliver the IP address of the DNS server on the public network to STAs so that the STAs can send DNS Request packets to the DNS server on the public network. To check the DNS configuration, run the display current-configuration | include dns ...
If set to Auto (the default), it will only prevent it if either DNSPrivacy or DNSFilter in global mode are enabled.(b6) DNS Privacy Protocol: You can configure your router to use a third party DNS server that supports encryption to prevent snooping on your DNS queries. While this ...
This document describes the configurations of Security, including ACL, Local Attack Defense, MFF, Attack Defense, Traffic Suppression and Storm Control, ARP Security, Port Security, DHCP Snooping, ND Snooping, IPv6 RA Guard, PPPoE+, IPSG, SAVI, PKI, OLC, Separati...
(b6) DNS Privacy Protocol: You can configure your router to use a third party DNS server that supports encryption to prevent snooping on your DNS queries. While this increases privacy, note that it might decrease general DNS performance. ...
ports in a VLAN that is serviced by DHCP. Before you turn on DHCP Snooping on the VLAN you want to protect, you need to set up the trusted ports. These are the ports through which real DHCP server messages will flow. Both the CLI interface and the Web GUI can be used to do this....