Cisco WS-C6506 Software Manual page 721

Chapter 23 Configuring Redundancy
PFC2: The PFC2 supports a maximum of 16 unique HSRP group numbers. You can use the same HSRP
Note
group numbers in different VLANs. If you configure more than 16 HSRP groups, this restriction
prevents use of the VLAN number as the HSRP group number.
PFC2: Identically numbered HSRP groups use the same virtual MAC address, which might cause errors
Note
if you configure bridging on the MSFC.
Do not enter the standby use-bia option in an HSRP configuration. The MLS entries are not created
when you enter the standby use-bia option. When the standby use-bia option is configured, if an HSRP
active interface goes up and down, there will be no router CAM address for the standby VLAN interface.
Without the router CAM entry, no shortcuts are created. This problem is independent of any MSFC Cisco
IOS release. (This problem is documented in caveat CSCdz17169.)
To configure HSRP on an MSFC VLAN interface, perform this task in interface configuration mode:
Task
Step 1 Enable HSRP and specify the HSRP IP
address. If you do not specify a
group_number, group 0 is used. To assist in
troubleshooting, configure the group number
to match the VLAN number.
Step 2 Specify the priority for the HSRP interface.
Increase the priority of at least one interface
in the HSRP group (the default is 100). The
interface with the highest priority becomes
active for that HSRP group.
Step 3 Configure the interface to preempt the current
active HSRP interface and become active if
the interface priority is higher than the
priority of the current active interface.
Step 4 (Optional) Set the HSRP hello timer and
holdtime timer for the interface. The default
values are 3 (hello) and 10 (holdtime). All
interfaces in the HSRP group should use the
same timer values.
Step 5
(Optional) Specify a clear-text HSRP
authentication string for the interface. All
interfaces in the HSRP group should use the
same authentication string.
OL-8978-04
Command
Router(config-if)# standby [group_number] ip [ip_address]
Router(config-if)# standby [group_number] priority priority
Router(config-if)# standby [group_number] preempt [delay
delay]
Router(config-if)# standby [group_number] timers hellotime
holdtime
Router(config-if)# standby [group_number] authentication
string
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
MSFC Redundancy
23-29