4.10.5 Configuring ARP Update Triggered by Changes in the
Outbound Interfaces of the VRRP Virtual MAC Address
This section describes how to configure Address Resolution Protocol (ARP) update triggered
by changes in the outbound interfaces of the Virtual Router Redundancy Protocol (VRRP) virtual
MAC address.
Context
Two routers are dual-homed to the master and backup devices in a VRRP backup group to form
a ring network. After the upstream devices perform a master/backup VRRP switchover, the
router may not receive gratuitous ARP packets from the master device in the VRRP backup
group to update the ARP entries. The outbound interfaces have changed, however, the router
can learn new ARP entries only after the existing ARP entries age out. This process may cause
packet loss for a long time and therefore services are interrupted. To resolve this issue, configure
ARP update triggered by changes in the outbound interfaces of the VRRP virtual MAC address.
This configuration allows the router to update ARP entries after receiving VRRP heartbeat
packets that are sent due to the changes in the outbound interfaces of the virtual MAC address.
As a result, traffic can be forwarded properly.
NOTE
If VRRP heartbeat packets are not forwarded through the router, this configuration cannot help detect the
change of a MAC entry carrying the virtual MAC address of a VRRP backup group. To update ARP entries
on the VLANIF interface on the router, enable the router to send ARP probe packets so that it can update
the outbound interfaces in ARP entries.
Perform the following steps on the router:
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
interface
vlanif
vlan-id
The VLANIF interface view is displayed.
Step 3
Run:
mac trigger-arp-update
ip-address
enable
[
suppress-interval
suppress-interval
]
ARP update triggered by changes in the outbound interfaces of the VRRP virtual MAC address
is configured on the VLANIF interface.
Step 4
(Optional) Run:
arp-detect
ip-address
enable
The VLANIF interface is enabled to send ARP probe packets.
Step 5
(Optional) Run:
arp-detect
interval
seconds
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
4 VRRP Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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