Key points for configuring PIX dual-Machine failover

1, to find out about the "master" the "preparation" of several concepts:

Failover Link

Failover link is used to communicate each other's working status between devices, and the information passed on Failover link includes:

o Current status of the device (active and Standby)

O Power status (only based on dedicated failover cable)

o Hello packet (also sent via all other ports)

o The active device passes configuration to the standby device (called Configuration synchronization)

Failover link can use two kinds of media (form different Failover forms)

O This is recommended when you are based on a dedicated cable ("cable-based failover")-two devices with distances not exceeding 6 feet (about 1.83 meters). Because the device can perceive each other's power status through this cable, and can tell whether the device is powered down or not plugged in at all. The failover cable is an improved RS-232 serial cable (Kbps), one end labeled "Primary" to connect to the Primary device, and the other end labeled "secondary" to connect to the secondary device.

O Ethernet ("lan-based failover")-you can use any unused Ethernet port on your device, in this way when the two devices are more than 6 feet (about 1.83 meters) away. Note that this method must be connected through the switch (the recommended use of a separate switch), and not directly connected to the Ethernet port of the two machines through the crossover line.

The disadvantages of Ethernet based failover link include:

• It takes longer to failover when a power failure occurs

The configuration of the standby device needs to be set separately (in cable-based failover, the standby device can communicate with an active device without having to enable any port or IP address, and accept the entire configuration information from an active device. ）

• Switch between two devices for failover link becomes the point of failure of another hardware

• Consuming Ethernet ports

The advantages of failover link based on Ethernet:

• Equipment can be 6 feet apart

• Configure synchronization faster

(In lan-based failover, if failover link is broken, other ports are automatically used to view the other state.) ）

Primary, secondary and active, Standby

The former is the physical concept, the latter is the logical concept.

The device that is currently responsible for forwarding network traffic is an active device and the other is a standby device.

In cable-based failover, the primary end of the cable is connected to the primary device; the secondary-side-connected Pix is called the sencondary device; in lan-based failover, The primary and Sencondary devices are set in the configuration file.

When both devices are started simultaneously and are in a healthy state, the primary device is an active device, and when the primary device fails, the failover event occurs and the Seconary device becomes an active device.