ZyXEL Communications 200 Series - Manual (Page 588)

Chapter 34 Device HA
ZyWALL USG 100/200 Series User’s Guide
588
Figure 439 Example: VRRP, Normal Operation
The VR ID is not shown. In normal operation, ZyWALL A is the master. It has the same IP
address as the default gateway and forwards traffic for the network. ZyWALL B is a backup. It
is using its management IP address 192.168.10.112. ZyWALL A sends regular messages to
ZyWALL B to let ZyWALL B know that ZyWALL A is available. If ZyWALL A becomes
unavailable, it stops sending messages to ZyWALL B. ZyWALL B detects this and assumes
the role of the master. This is illustrated below.
Figure 440 Example: VRRP, Master Becomes Unavailable
ZyWALL B is now using the IP address of the default gateway, and it is forwarding packets
for the network. The loss of ZyWALL A has no effect on the network.
If there is more than one backup ZyWALL, the backup ZyWALL with the highest priority
becomes the master. The other backup ZyWALLs remain backups.
If ZyWALL A becomes available again, ZyWALL A preempts ZyWALL B and becomes the
master again (the network returns to the state shown in
Figure 439 on page 588 ).
Synchronization
During synchronization, the master ZyWALL sends the following information to the backup
ZyWALL.
• Startup configuration file (startup-config.conf)
• AV signatures
• IDP and application patrol signatures
192.168.10.112