Route Preferences Configuration - Dell PowerConnect 8024 User Manual

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 9-34. IP Configured Routes Command
CLI Command
show ip route

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
NOTE: For a static reject route, the next hop interface value is Null0. Packets to the network address specified in
static reject routes are intentionally dropped.
To display the page, click Routing → Router → Route Preferences Configuration in the tree view.
Description
Displays the routing table.
Configuring Routing
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