Switch 7700 Configuration Guide

204 CHAPTER 10: RELIABILITY
Perform the following configuration in VLAN interface view.
The delay ranges from 0 to 255, measured in seconds. The default mode is
preemption with a delay of 0 second.
Note: If the preemption mode is cancelled, the delay time automatically becomes
0 seconds.
Configuring
Authentication Type and
Authentication Key
VRRP provides following authentication types:
■ simple: Simple character authentication
■ md5: MD5 authentication
In a network under possible security threat, the authentication type can be set to
simple. Then the switch adds the authentication key to the VRRP packets before
transmitting it. The receiver compares the authentication key of the packet to the
locally configured authentication key. If they are the same, the packet is accepted
as a true and legal one. If the keys are not the same the packet is considered illegal
and is discarded. A simple authentication key should not exceed 8 characters.
In an unsafe network, the authentication type can be set to md5. The switch uses
the authentication type and MD5 algorithm provided by the authentication header
to authenticate VRRP packets. An md5 authentication key should not exceed 16
Packets that fail to pass the authentication test are discarded and a trap packet is
sent to the network management system.
Perform the following configuration in VLAN interface view.
Note: The same authentication type and authentication key should be configured
for all vlan interfaces that belong to the virtual router.
Configuring the VRRP
Timer
The Master switch advertises its normal operation state to the switches within the
VRRP virtual router by sending them VRRP packets regularly (at adver-interval). If
the backup switch does not receive a VRRP packet from the master after a period
of time (specified by master-down-interval), the master is assumed to have failed
and the backup switch takes the role of master.
You can use the following command to set a timer and adjust the interval,
adver-interval at which the master transmits VRRP packets. The duration of the
Tab le 3 Configure Preemption and Delay for a Switch
Operation Command
Enable the preemption mode and
configure a period of delay.
vrrp vrid virtual-router-ID preempt-mode [ timer
delay delay-value ]
Disable the preemption mode. undo vrrp vrid virtual-router-ID preempt-mode
Tab le 4 Configure Authentication Type and Authentication Key.
Operation Command
Configure authentication type and
authentication key.
vrrp authentication-mode type [ key ]
Clear authentication type and
authentication key.
undo vrrp authentication-mode