3Com Switch 8800 Family Configuration Guide

Configuring VRRP 655
Enabling/Disabling the
Function to Ping the
Virtual IP Address
This operation enables or disables the function to ping the virtual IP address of the
virtual router. The standard protocol of VRRP does not support the ping function,
then the user cannot judge with ping command whether an IP address is used by
the virtual router. If the user configure the IP address for the host same as the
virtual IP address of the virtual router, then all messages in this segment will be
forwarded to the host.
So 3Com Switch 8800 Family Series Routing Switches (hereinafter referred to as
Switch 8800 Family series) provide the ping function to ping the virtual IP address
of the virtual router.
Perform the following configuration in system view.
By default, the function to ping the virtual IP address is enabled.
You should set the ping function before configuring the virtual router. If a virtual
router is already established on the switch, it is not allowed to use the vrrp
ping-enable command and the undo vrrp ping-enable command to modify the
configuration any more.
Enabling/Disabling the
Check of TTL Value of
VRRP Packet
This operation configures whether to check TTL value of VRRP packet on the
Backup switch. The TTL value must be 225. If the Backup switch find TTL is not
225 when receiving VRRP packet, the packet will be discarded.
Perform the following configuration in VLAN interface view.
By default, the switch checks TTL value of VRRP packets.
Setting Correspondence
between Virtual IP
Address and MAC
Address
This operation sets correspondence between the virtual lP address and the MAC
address. In the standard protocol of VRRP, the virtual IP address of the virtual
router corresponds to the virtual MAC address, to ensure correct data forwarding
in the sub-net.
Due to the chips installed, some switches support matching one IP address to
multiple MAC addresses.
Switch 8800 Family series not only guarantee correct data forwarding in the
sub-net, but also support such function: the user can choose to match the virtual
IP address with the real MAC address or virtual MAC address of the routing
interface.
Tab le 592 Enable/disable the ping function
Operation Command
Enable to ping the virtual IP address vrrp ping-enable
Disable to ping the virtual IP address undo vrrp ping-enable
Tab le 593 Enable/disable the check of TTL value of VRRP packet
Operation Command
Disable the check of TTL value of VRRP packet vrrp un-check ttl
Enable the check of TTL value of VRRP packet undo vrrp un-check ttl