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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
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Configuring HSRP
This chapter describes how to use Hot Standby Router Protocol (HSRP) on the switch to provide routing
redundancy for routing IP traffic without being dependent on the availability of any single router.Unless
otherwise noted, the term
switch
refers to a standalone switch and to a switch stack.
Note
For complete syntax and usage information for the commands used in this chapter, see the switch
command reference for this release and the
Cisco IOS IP Command Reference, Volume 1 of 3:
Addressing and Services, Release 12.2
.
This chapter consists of these sections:
•
•
•
Displaying HSRP Configurations, page 40-12
Understanding HSRP
HSRP is Cisco’s standard method of providing high network availability by providing first-hop
redundancy for IP hosts on an IEEE 802 LAN configured with a default gateway IP address. HSRP
routes IP traffic without relying on the availability of any single router. It enables a set of router
interfaces to work together to present the appearance of a single virtual router or default gateway to the
hosts on a LAN. When HSRP is configured on a network or segment, it provides a virtual Media Access
Control (MAC) address and an IP address that is shared among a group of configured routers. HSRP
allows two or more HSRP-configured routers to use the MAC address and IP network address of a virtual
router. The virtual router does not exist; it represents the common target for routers that are configured
to provide backup to each other. One of the routers is selected to be the active router and another to be
the standby router, which assumes control of the group MAC address and IP address should the
designated active router fail.
Note
Routers in an HSRP group can be any router interface that supports HSRP, including routed ports and
switch virtual interfaces (SVIs).
HSRP provides high network availability by providing redundancy for IP traffic from hosts on networks.
In a group of router interfaces, the active router is the router of choice for routing packets; the standby
router is the router that takes over the routing duties when an active router fails or when preset conditions
are met.