Disable the Dynamic Host Configuration Protocol (DHCP) server and relay agent features on your router. Rationale: The DHCP server supplies automatic configuration parameters, such as dynamic IP address, to requesting systems. A dedicated server located in a secured management zone should be used to provide DHCP services instead. Attackers can potentially be used for denial-of-service (DoS) attacks.
Solution
Disable the DHCP server. hostname(config)#<strong>no service dhcp</strong> Impact: To reduce the risk of unauthorized access, organizations should implement a security policy restricting network protocols and explicitly require disabling all insecure or unnecessary protocols such as the Dynamic Host Configuration Protocol (DHCP). Default Value: Enabled by default, but also requires a DHCP pool to be set to activate the DHCP server. References: http://www.cisco.com/en/US/docs/ios-xml/ios/ipaddr/command/ipaddr-r1.html#GUID-1516B259-AA28-4839-B968-8DDBF0B382F6