Avaya P332GT-ML, Installation And Configuration Manual

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Chapter 12 Avaya P330 Layer 3 Features
110 Avaya P332GT -ML User’s Guide
SRRP Configuration
SRRP Overview
Avaya P330 IP SRRP redundancy capabilities provide automatic backup Layer 3
switching for IP stations. P330 units can be configured to back each other up so that
if one fails the other will take over its forwarding functions. The backup P330 is not
idle. As long as both P330 units are functional, traffic is shared between them. The
P330 can back up another P330 unit or any other router.
A P330 unit configured to back up another unit monitors the other's status by
polling it at configured intervals, and automatically detects when the other fails and
when it becomes functional again. When detecting a failure, the backup P330 sends
a gratuitous ARP message that causes all stations to send their IP traffic to the
backup P330 MAC address instead of the failed unit MAC address. As long as it is
an active backup resulting from the failure of the main unit, the backup P330
answers ARP requests for the main unit, providing its own MAC address
SRRP Configuration Example
• The P330 in SRRP mode can backup any other router
• The integrity of the main router is checked via periodic ping polling (default
period is 3 sec.)
• When the backup router doesn’t receive ping response after pre-configured
period (default 12 sec.), the backup sends an ARP request (broadcast)
advertising the failed router IP address with its’ own MAC, so all the stations
will start to direct their packets to the new MAC.
IP: 20.20.20.10
DG: 20.20.20.2
IP: 20.20.20.20
DG: 20.20.20.2
Main Router
IP: 20.20.20.2
P330 - Backup Router
IP: 20.20.20.1