Determining Which Type Of Failover To Use; Regular And Stateful Failover; Regular Failover; Stateful Failover - Cisco PIX 500 Series Configuration Manual

Chapter 14 Configuring Failover

Determining Which Type of Failover to Use

The type of failover you choose depends upon your security appliance configuration and how you plan
to use the security appliances.
If you are running the security appliance in single mode, then you can only use Active/Standby failover.
Active/Active failover is only available to security appliances running in multiple context mode.
If you are running the security appliance in multiple context mode, then you can configure either
Active/Active failover or Active/Standby failover.
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•
Table 14-3
configuration:
Table 14-3
Feature
Single Context Mode
Multiple Context Mode
Load Balancing Network Configurations
Unit Failover
Failover of Groups of Contexts
Failover of Individual Contexts

Regular and Stateful Failover

The security appliance supports two types of failover, regular and stateful. This section includes the
following topics:
•
•

Regular Failover

When a failover occurs, all active connections are dropped. Clients need to reestablish connections when
the new active unit takes over.

Stateful Failover

When Stateful Failover is enabled, the active unit continually passes per-connection state information to
the standby unit. After a failover occurs, the same connection information is available at the new active
unit. Supported end-user applications are not required to reconnect to keep the same communication
session.
The state information passed to the standby unit includes the following:
•
•
OL-12172-03
To provide load balancing, use Active/Active failover.
If you do not want to provide load balancing, use Active/Standby or Active/Active failover.
provides a comparison of some of the features supported by each type of failover
Failover Configuration Feature Support
Regular Failover, page 14-15
Stateful Failover, page 14-15
NAT translation table.
TCP connection states.
Active/Active
No
Yes
Yes
Yes
Yes
No
Cisco Security Appliance Command Line Configuration Guide
Understanding Failover
Active/Standby
Yes
Yes
No
Yes
No
No
14-15