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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
OL-13270-01
Chapter38 Configuring IP Unicast Routing
Configuring Protocol-Independent Features
router to intelligently discriminate between sources of routing in formation. The router always picks the
route whose routing protocol has the lowest administrative distance. Table 38-14 on page 38-84 shows
the default administrative distances for various routing information sources.
Because each network has its own requirements, there are no general guidelines for assigning
administrative distances.
Beginning in privileged EXEC mode, follow these steps to filter sources of routing information:
To remove a distance definition, use the no distance router configuration command.
Managing Authentication Keys
Key management is a method of controlling authentication keys used by routing protocols. Not all
protocols can use key management. Authentication keys are available for EIGRP and RIP Version 2.
Before you manage authentication keys, you must enable authentication. See the appropriate protocol
section to see how to enable authentication for that protoc ol. To manage authentic ati on keys, define a
key chain, identify the keys that belong to the key chain, and specify how long each key is valid. Each
key has its own key identifier (specified with the key number key chain configuration command), which
is stored locally. The combination of the key identifier and the interface associated with the message
uniquely identifies the authentication algorithm and Message Digest 5 (MD5) authe ntication key in use.
You can configure multiple keys with life times. Only one authentication packet is sent, regardless of
how many valid keys exist. The software examines the key numbers in order from lowest to highest, and
uses the first valid key it encounters. The lifetimes allow for overlap during key changes. Note that the
router must know these lifetimes.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 router {bgp | rip | ospf | eigrp} Enter router configuration mode.
Step3 distance weight {ip-address {ip-address mask}}
[ip access list]Define an administrative distance.
weight—The administrative distance as an integer from
10 to 255. Used alone, weight specifies a default
administrative distance that is used when no other
specification exists for a routing information source.
Routes with a distance of 255 are not installed in the
routing table.
(Optional) ip access list—An IP standard or extended
access list to be applied to incoming routing updates.
Step4 end Return to privileged EXEC mode.
Step5 show ip protocols Display the default administrative distance for a
specified routing process.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.