Specifications

Chapter 2. IBM System Networking Switch 10Gb Ethernet switch features 85
A virtual router group has the following characteristics:
򐂰 When enabled, all virtual routers behave as one entity, and all group settings override any
individual virtual router settings.
򐂰 All individual virtual routers, after the VRRP group is enabled, assume the group’s tracking
and priority.
򐂰 When one member of a VRRP group fails, the priority of the group decreases, and the
state of the entire switch changes from Master to Standby.
Each VRRP advertisement can include up to 16 addresses. All virtual routers are advertised
within the same packet, conserving processing and buffering resources.
High-availability configurations
Figure 2-16 shows an example configuration where two IBM System Networking switches are
used as VRRP routers in an active-active configuration. In this configuration, both switches
respond to packets.
Figure 2-16 Active-active configuration with VRRP
Although this example shows only two switches, there is no limit of the number of switches
used in a redundant configuration. It is possible to implement an active-active configuration
across all the VRRP-capable switches in a LAN.
Each VRRP-capable switch in an active-active configuration is autonomous. Switches in a
virtual router do not need to be identically configured.
In the scenario illustrated in Figure 2-16, traffic destined for IPv4 address 10.0.1.1 is
forwarded through the Layer 2 switch at the top of the drawing, and ingresses Switch 1 on
port 1. Return traffic uses default gateway 1 (192.168.1.1).
If the link between Switch 1 and the Layer 2 switch fails, Switch 2 becomes the master
because it has a higher priority. Traffic is forwarded to Switch 2, which forwards it to Switch 1
through port 4.
Return traffic uses default gateway 2 (192.168.2.1), and is forwarded through the Layer 2
switch at the bottom of the drawing.