Specifications

Configuring Routing Between VLANs
Configuration Examples for Configuring Routing Between VLANs
55
Figure 85 Hot Standby Router Protocol Sample Configuration
The topology shown in Figure 85 shows a Catalyst VLAN switch supporting Fast Ethernet connections
to two routers running HSRP. Both routers are configured to route HSRP over ISLs.
The standby conditions are determined by the standby commands used in the configuration. Traffic from
Host 1 is forwarded through Router A. Because the priority for the group is higher, Router A is the active
router for Host 1. Because the priority for the group serviced by Host 2 is higher in Router B, traffic from
Host 2 is forwarded through Router B, making Router B its active router.
In the configuration shown in Figure 85, if the active router becomes unavailable, the standby router
assumes active status for the additional traffic and automatically routes the traffic normally handled by
the router that has become unavailable.
Host 1 Configuration
interface Ethernet 1/2
ip address 10.1.1.25 255.255.255.0
ip route 0.0.0.0 0.0.0.0 10.1.1.101
Host 2 Configuration
interface Ethernet 1/2
ip address 10.1.1.27 255.255.255.0
ip route 0.0.0.0 0.0.0.0 10.1.1.102
!
Router A Configuration
interface FastEthernet 1/1.110
encapsulation isl 110
ip address 10.1.1.2 255.255.255.0
standby 1 ip 10.1.1.101
standby 1 preempt
standby 1 priority 105
standby 2 ip 10.1.1.102
standby 2 preempt
S6239
Enterprise
network
HSRP peers
FE 1/1FE 1/1
Port 2/8
Port 5/3
Port 2/9
Port 5/4
ISL VLAN 110
Catalyst VLAN
switch
Ethernet 1/2
Ethernet 1/2
Ethernet 1/2
Ethernet 1/2
Host 1 Host 2
Cisco IOS Router A
on FastEthernet
ISL connection to a
Catalyst 5000 switch
Cisco IOS Router B
on FastEthernet
ISL connection to a
Catalyst 5000 switch
Cisco IOS
Cisco IOS