Restrictions For Vtp; Information About Vtp; Vtp - Cisco Catalyst 2960 series Configuration Manual

Restrictions for VTP

database occur simultaneously on switches in the same domain, which would result in an inconsistency in the
VLAN database.
The switch supports a total of 1000 VLANs. However, the number of routed ports, SVIs, and other configured
features affects the usage of the switch hardware. If the switch is notified by VTP of a new VLAN and the
switch is already using the maximum available hardware resources, it sends a message that there are not
enough hardware resources available and shuts down the VLAN. The output of the show vlan user EXEC
command shows the VLAN in a suspended state.
Because trunk ports send and receive VTP advertisements, you must ensure that at least one trunk port is
configured on the switch or switch stack and that this trunk port is connected to the trunk port of another
switch. Otherwise, the switch cannot receive any VTP advertisements.

Restrictions for VTP

Note Before adding a VTP client switch to a VTP domain, always verify that its VTP configuration revision
number is lower than the configuration revision number of the other switches in the VTP domain. Switches
in a VTP domain always use the VLAN configuration of the switch with the highest VTP configuration
revision number. If you add a switch that has a revision number higher than the revision number in the
VTP domain, it can erase all VLAN information from the VTP server and VTP domain.
The following are restrictions for configuring VTPs:
• 1K VLAN is supported only on switches running the LAN Base image with the lanbase-default template
• To avoid warning messages of high CPU utilization with a normal-range VLAN configuration, we

Information About VTP

VTP

VTP is a Layer 2 messaging protocol that maintains VLAN configuration consistency by managing the
addition, deletion, and renaming of VLANs on a network-wide basis. VTP minimizes misconfigurations and
configuration inconsistencies that can cause several problems, such as duplicate VLAN names, incorrect
VLAN-type specifications, and security violations.
VTP functionality is supported across the stack, and all switches in the stack maintain the same VLAN and
VTP configuration inherited from the active switch. When a switch learns of a new VLAN through VTP
messages or when a new VLAN is configured by the user, the new VLAN information is communicated to
all switches in the stack.
When a switch joins the stack or when stacks merge, the new switches get VTP information from the active
switch.
Catalyst 2960-X Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX
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set.
recommended to have no more than 256 VLANs.
In such cases, approximately 10 access interfaces or 5 trunk interfaces can flap simultaneously with
negligible impact to CPU utilization (if there are more interfaces that flap simultaneously, then CPU
usage may be excessively high.)
Configuring VTP
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