Cisco 7604 Configuration Manual page 279

Chapter 14 Configuring Failover
Enabling HTTP Replication with Stateful Failover
To allow HTTP connections to be included in the state information replication, you need to enable HTTP
replication. Because HTTP connections are typically short-lived, and because HTTP clients typically
retry failed connection attempts, HTTP connections are not automatically included in the replicated state
information.
Enter the following command in global configuration mode to enable HTTP state replication when
Stateful Failover is enabled:
hostname(config)# failover replication http
Configuring Interface and Unit Poll Times
FWSM monitors both unit and interface health for failover. You can configure the amount of time
between hello messages when monitoring interface and unit health. Decreasing the poll time allows an
interface or unit failure to be detected more quickly, but consumes more system resources.
To change the interface poll time, enter the following command in global configuration mode:
hostname(config)# failover polltime interface seconds
To change the unit poll time, enter the following command in global configuration mode:
hostname(config)# failover polltime seconds
To change the unit hold time, enter the following command in global configuration mode:
hostname(config)# failover holdtime seconds
The defaults are as follows:
•
•
•
You cannot enter a holdtime value that is less than 3 times the unit poll time. With a faster poll time, the
Note
FWSM can detect failure and trigger failover faster. However, faster detection can cause unnecessary
switchovers when the network is temporarily congested.
Configuring Failover Criteria
By default, failure of 50% of monitored interfaces causes failover. You can specify a specific number of
interfaces or a percentage of monitored interfaces that must fail before a failover occurs.
To change the default failover criteria, enter the following command in global configuration mode:
hostname(config)# failover interface-policy num[%]
When specifying a specific number of interfaces, the num argument can be from 1 to 250. When
specifying a percentage of interfaces, the num argument can be from 1 to 100.
Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
OL-20748-01
The interface poll time is 15 seconds.
The unit poll time is 1 second.
The holdtime time is 3 times the poll time (with a minimum value of 3 seconds) if you specify a
poll time but do not specify a hold time with the holdtime keyword. If you specify a hold time using
the holdtime keyword, it must be at least 3 times the poll time. If you enter the clear configure
failover command, the hold time is 15 seconds.
Configuring Failover
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