Avaya 580 - Manual (Page 195)

Document No. 10-300077, Issue 2 6-29
Using VLANs, Hunt Groups, and VTP Snooping
Configuring VTP Snooping
Enabling VLAN Trunk Protocol (VTP®) Snooping on the Avaya
Multiservice switch allows it to automatically synchronize its VLAN
configuration with that of a Cisco VTP server switch. VTP is a Cisco®
layer 2 protocol used to maintain VLAN configuration consistency among
switches. Both switches must be on the same network, have at least VLAN
1 (Default) bound to a connecting link that is forwarding according to the
Spanning Tree Protocol, and both ends of the link have the same Trunk
Mode setting. Valid Trunk Mode options that work with VTP Snooping are
Cisco Inter-Switch Link (Multi-layer) and IEEE 802.1Q.
VLAN additions, deletions, and name changes made on the network's Cisco
VTP server are automatically updated on Avaya Multiservice switches that
have VTP Snooping enabled and are connected to the Cisco VTP server
with the same VTP Domain name. VLAN changes made on an Avaya
Multiservice switch are not automatically updated on any other switch.
Please note that VTP- learned VLANs may not be modified or deleted on an
Avaya Multiservice switch while VTP is enabled. This restriction is in place
to help maintain VLAN configuration consistency among VTP Snooping
switches within the VTP Domain. Also the Avaya Multiservice switch
handles VLAN name or VLAN ID conflicts between itself and a VTP
server by giving locally configured VLANs precedence. For example if a
VLAN ID or VLAN name is received in a VTP message that is also
configured locally on an Avaya Multiservice switch, the VTP message's
VLAN information is ignored for that VLAN and a message is entered in
the switch's event log indicating the condition.
* Note: When VTP Snooping creates VLANs on the Avaya
Multiservice switches, the hash table size for the VLANs is
automatically set to 64. Depending on the number of VLANs
that are created, you may need to manually change this hash
table setting. For information on the relationship between hash
table sizes and the number of VLANs that are configured on the
switch, see “
Relationship between VLANs, AFT and Hash
Table Sizes ,” in Chapter 9 , “ Managing the Address Forwarding
Table .”
VTP Snooping is Disabled by default. You only need to change VTP
Snooping port settings if you want to Enable its ability to learn VLAN
changes from a Cisco VTP server.
You can configure VTP snooping from either the Web Agent or the CLI.