Vtp version 2, Vtp pruning – Dell POWEREDGE M1000E User Manual

Page 404

Advertising
background image

14-4

Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide

OL-13270-03

Chapter 14 Configuring VTP

Understanding VTP

VTP advertisements distribute this global domain information:

VTP domain name

VTP configuration revision number

Update identity and update timestamp

MD5 digest VLAN configuration, including maximum transmission unit (MTU) size for each
VLAN.

Frame format

VTP advertisements distribute this VLAN information for each configured VLAN:

VLAN IDs (ISL and IEEE 802.1Q)

VLAN name

VLAN type

VLAN state

Additional VLAN configuration information specific to the VLAN type

VTP Version 2

If you use VTP in your network, you must decide whether to use Version 1 or Version 2. By default,
VTP operates in Version 1.

VTP Version 2 supports these features that are not supported in Version 1:

Token Ring support—VTP Version 2 supports Token Ring Bridge Relay Function (TrBRF) and
Token Ring Concentrator Relay Function (TrCRF) VLANs. For more information about Token
Ring VLANs, see the

“Configuring Normal-Range VLANs” section on page 13-4

.

Unrecognized Type-Length-Value (TLV) support—A VTP server or client propagates
configuration changes to its other trunks, even for TLVs it is not able to parse. The unrecognized
TLV is saved in NVRAM when the switch is operating in VTP server mode.

Version-Dependent Transparent Mode—In VTP Version 1, a VTP transparent switch inspects VTP
messages for the domain name and version and forwards a message only if the version and domain
name match. Because VTP Version 2 supports only one domain, it forwards VTP messages in
transparent mode without inspecting the version and domain name.

Consistency Checks—In VTP Version 2, VLAN consistency checks (such as VLAN names and
values) are performed only when you enter new information through the CLI or SNMP. Consistency
checks are not performed when new information is obtained from a VTP message or when
information is read from NVRAM. If the MD5 digest on a received VTP message is correct, its
information is accepted.

VTP Pruning

VTP pruning increases network available bandwidth by restricting flooded traffic to those trunk links
that the traffic must use to reach the destination devices. Without VTP pruning, a switch floods
broadcast, multicast, and unknown unicast traffic across all trunk links within a VTP domain even
though receiving switches might discard them. VTP pruning is disabled by default.

Advertising