Cisco 3032 - Configuring the Number of Equal-Cost Routing Paths

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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
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Chapter 38 Configuring IP Unicast Routing
Configuring Protocol-Independent Features
Configuring the Number of Equal-Cost Routing Paths
When a router has two or more routes to the same network with the same metrics, these routes can be
thought of as having an equal cost. A parallel path provides another way to see occurrences of equal-cost
routes in an IP routing table. A router with two or more equal-cost paths to a network can use them
concurrently. Parallel paths provide redundancy in case of a circuit failure and also enable a router to
load balance packets for more efficient use of available bandwidth. Equal-cost routes are supported
across switches in a stack.
The router automatically learns about and configures equal-cost routes, but you can control the
maximum number of parallel paths supported by an IP routing protocol in its routing table. Although the
switch software allows a maximum of 32 equal-cost routes, the switch never uses more than 16 paths per
route.
Beginning in privileged EXEC mode, follow these steps to change the maximum number of parallel
paths in a routing table from the default:
Use the no maximum-paths router configuration command to restore the default value.
Step 7
show cef linecard [detail]
or
show cef linecard [stack-member-number]
[detail]
Display CEF-related interface information on a standalone
switch,
or
display dCEF-related interface information for all switches in
the stack or for the specified stack member.
(Optional) For stack-member-number, specify the stack
member.
Step 8
show cef interface [interface-id] Display detailed CEF information for all interfaces or the
specified interface.
Step 9
show adjacency Display CEF adjacency table information.
Step 10
copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
router {bgp | rip | ospf | eigrp} Enter router configuration mode.
A switch running the IP base feature set supports only the rip keyword.
Step 3
maximum-paths maximum Set the maximum number of parallel paths for the protocol routing
table. The range is from 1 to 16; the default is 4 for most IP routing
protocols, but only 1 for BGP.
Step 4
end Return to privileged EXEC mode.
Step 5
show ip protocols Verify the setting in the Maximum path field.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.