Avaya P332G-ML Manual Do Utilizador

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Chapter 12        Avaya P330 Layer 3 Features
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Avaya P332G-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
MAC: CD.EF.AB.CD.EF.AB
P330 - Backup Router
IP: 20.20.20.1
MAC: AB.CD.EF.AB.CD.EF