D-Link DWS-4026 Product Manual - Page 312

D-Link Unified Access System Software User Manual 12/10/09 VIRTUAL ROUTER REDUNDANCY PROTOCOL (VRRP) The Virtual Router Redundancy protocol is designed to handle default router failures by providing a scheme to dynamically elect a backup router. The driving force was to minimize "black hole" periods due to the failure of the default gateway router during which all traffic directed towards it is lost until the failure is detected. Though static configuration of default routes is popular, such an approach is susceptible to a single point of failure when the default router fails. VRRP advocates the concept of a "virtual router" associated with one or more IP Addresses that serve as default gateways. In the event that the VRRP Router controlling these IP Addresses (formally known as the Master) fails, the group of IP Addresses and the default forwarding role is taken over by a Backup VRRP Router. The LAN > L3 Features > VRRP folder and LAN > Monitoring > L3 Status folder contain links to the following web pages that configure and display VRRP parameters and data: • "VRRP Configuration" • "Virtual Router Configuration" • "Virtual Router Status" • "Virtual Router Statistics" VRRP CONFIGURATION Use the VRRP Configuration page to enable or disable the administrative status of a virtual router. To display the page, click LAN > L3 Features > VRRP > VRRP Configuration in the navigation tree. Figure 217: VRRP Configuration Field Admin Mode Table 196: VRRP Configuration Description This sets the administrative status of VRRP in the router to active or inactive. Select Enable or Disable from the dropdown menu. The default is Disable. • If you change the administrative mode, click Submit to apply the changes to the system. Page 312 Virtual Router Redundancy Protocol (VRRP) Document 34CSFP6XXUWS-SWUM100-D7