Nortel Networks WEB OS 212777 - Manual (Page 255)

Web OS 10.0 Application Guide
Chapter 11: High Availability n 255
212777-A, February 2002
Active-Active Redundancy
In an active-active configuration, two Web switches provide redundancy for each other, with
both active at the same time for the same services.
Web OS has extended VRRP to include virtual servers, allowing full active/active redundancy
between its Layer 4 switches. In an active-active configuration, shown in
Figure 11-5 , both
switches can process traffic for the same service at the same time; both switches can be active
simultaneously for a given IP routing interface or load-balancing virtual server (VIP).
Figure 11-5 Active-Active Redundancy
In the example above, one switch is still the master router. However, traffic going through the
backup router (associated with the same virtual router on the switch) that is addressed to the
master router will be intercepted and processed by the backup router.
Internet
Router
Router
Active VIP 1
VIP: 205.178.13.226
Active VIP 1
VIP: 205.178.13.226
Active VIP 2
VIP: 205.178.13.240
Active VIP 2
VIP: 205.178.13.240
Active VIP 3
VIP: 205.178.13.110
Active VIP 3
VIP: 205.178.13.110
Active
Active