Quick Reference Guide

PowerConnect B-Series TI24X Configuration Guide 219
53-1002269-02
Virtual Switch Redundancy Protocol (VSRP)
8
The PowerConnect support full VSRP and VSRP-awareness. A PowerConnect device that is not itself
configured for VSRP, but is connected to a PowerConnect device that is configured for VSRP, is
VSRP aware.
You can use VSRP for Layer 2, Layer 3, or for both layers. On Layer 3 Switches, Layer 2 and Layer 3
share the same VSRP configuration information. On Layer 2 Switches, VSRP applies only to Layer
2.
Figure 44 shows an example of a VSRP configuration.
FIGURE 44 VSRP mesh – redundant paths for Layer 2 and Layer 3 traffic
In this example, two devices are configured as redundant paths for VRID 1. On each of the devices,
a Virtual Router ID (VRID) is configured on a port-based VLAN. Since VSRP is primarily a Layer 2
redundancy protocol, the VRID applies to the entire VLAN. However, you can selectively remove
individual ports from the VRID if needed.
Following master election (described below), one of the devices becomes the master for the VRID
and sets the state of all the VLAN ports to Forwarding. The other device is a backup and sets all the
ports in its VRID VLAN to Blocking.
If a failover occurs, the backup becomes the new master and changes all its VRID ports to the
Forwarding state.
Other devices can use the redundant paths provided by the VSRP devices. In this example, three
devices use the redundant paths. A device that is not itself configured for VSRP but is connected to
a device that is configured for VSRP, is VSRP aware. In this example, the three devices connected
to the VSRP devices are VSRP aware. A device that is VSRP aware can failover its link to the new
master in sub-second time, by changing the MAC address associated with the redundant path.
When you configure VSRP, make sure each of the non-VSRP devices connected to the VSRP devices
has a separate link to each of the VSRP devices.
VSRP
Master
VSRP
Backup
optional link
VSRP
Aware
VSRP
Aware
VSRP
Aware
Hello packets
F
F
F
B
B
B