ZyXEL Communications 1050 - Device HA

ZyWALL (ZLD) CLI Reference Guide
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CHAPTER 22
Device HA
Use device HA and Virtual Router Redundancy Protocol (VRRP) to increase network
reliability.
22.1 Device HA Overview
This section provides an overview of VRRP, VRRP groups, and synchronization.
22.1.1 Virtual Router Redundancy Protocol (VRRP) Overview
Every computer on a network may send packets to a default gateway, which can become a
single point of failure. Virtual Router Redundancy Protocol (VRRP), allows you to create
redundant backup gateways to ensure that the default gateway is always available.
" The ZyWALL runs VRRP v2. You can only set up device HA with other
ZyWALLs of the same model running the same firmware version.
22.1.2 VRRP Group Overview
In the ZyWALL, you should create a VRRP group to add one of its interfaces to a virtual
router. You can add any Ethernet interface, VLAN interface, or virtual interface (created on
top of Ethernet interfaces or VLAN interfaces) with a static IP address. You can only enable
one VRRP group for each interface, and you can only have one active VRRP group for each
virtual router.
22.1.3 Synchronization Overview
In a virtual router, backup routers do not automatically get configuration updates from the
master router. In this case, the master ZyWALL router can send backup ZyWALL routers these
updates. This is called synchronization.