Chapter 11. Failover

Terms you'll need to understand:

• Primary firewall

• Secondary firewall

• Serial cable failover

• LAN-based failover

• Non-stateful failover

• Stateful failover

• Replication

• Primary firewall

Techniques you'll need to master:

• Configuring stateful firewalls

• Failing back

Previous chapters have talked about several features the PIX firewall can provide. These features can protect systems from access and reconnaissance attacks and enable you to control user access with AAA services. These features are excellent at what they do; however, they rely on one firewall connection. Therefore, that firewall must be functioning and online to allow traffic to flow. If that one firewall were to fail, all traffic would cease .

The PIX firewall addresses this single point of failure with a technology called failover . Failover enables two firewalls to work together to provide basic fault tolerance in the event the primary firewall fails. This chapter provides an overview of the failover feature offered by the PIX firewall.