Dell PowerConnect 6248 User's Guide - Page 581

Default - Enter the default gateway address in the Next Hop IP Address field. Figure 9-38 shows the fields that display when the Route Type value is Default. Static - Enter values for Network Address, Subnet Mask, Next Hop IP Address, and Preference. Figure 9-39 shows the fields that display when the Route Type value is Static. 4. Click Apply Changes. The new route is added, and you are returned to the Configured Routes page. Displaying Configured Routes Using CLI Commands For information about the CLI command that performs this function, see the following chapter in the CLI Reference Guide: • IP Routing Commands The following table summarizes the equivalent CLI commands for this feature. Table 9-35. IP Configured Routes Command CLI Command show ip route Description Displays the routing table. Route Preferences Configuration Use the Router Route Preferences Configuration page to configure the default preference for each protocol (for example 60 for static routes). These values are arbitrary values that range from 1 to 255, and are independent of route metrics. Most routing protocols use a route metric to determine the shortest path known to the protocol, independent of any other protocol. The best route to a destination is chosen by selecting the route with the lowest preference value. When there are multiple routes to a destination, the preference values are used to determine the preferred route. If there is still a tie, the route with the best route metric is chosen. To avoid problems with mismatched metrics (i.e. RIP and OSPF metrics are not directly comparable), you must configure different preference values for each of the protocols. Static Reject Routes A static reject route is a static route to discard the packets to a particular destination, thereby forcing a black-hole routing behavior for a particular set of IP prefixes. Static reject routes can help prevent a routing loop in the network if a default route is configured on a router. Static reject routes also help protect against a DOS attack on a router with unwanted destination addresses. NOTE: Static reject routes are not redistributed by OSPF or RIP. You can select Static Reject as a route type from the Route Type field on the following pages under the Routing →Router menu: • Route Entry Configuration • Configured Routes Configuring Routing 581