Cisco Catalyst 2960 Series, Configuration Manual

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• If you do not configure the persistent MAC address feature, when the new active switch is elected, it
sends a takeover message with the new active MAC address as the primary server.
• If a persistent MAC address is configured, the new active switch waits for the configured timer value.
If the previous active switch does not rejoin the stack during this time, then the new active switch issues
the takeover message.
VTP Configuration Guidelines
VTP Configuration Requirements
When you configure VTP, you must configure a trunk port so that the switch can send and receive VTP
advertisements to and from other switches in the domain.
VTP versions 1 and 2 do not support private VLANs. VTP version 3 does support private VLANs. If you
configure private VLANs, the switch must be in VTP transparent mode. When private VLANs are configured
on the switch, do not change the VTP mode from transparent to client or server mode.
VTP Settings
The VTP information is saved in the VTP VLAN database. When VTP mode is transparent, the VTP domain
name and mode are also saved in the switch running configuration file, and you can save it in the switch
startup configuration file by entering the
copy running-config startup-config privileged EXEC command.
You must use this command if you want to save VTP mode as transparent, even if the switch resets.
When you save VTP information in the switch startup configuration file and reboot the switch, the switch
configuration is selected as follows:
• If the VTP mode is transparent in the startup configuration and the VLAN database and the VTP domain
name from the VLAN database matches that in the startup configuration file, the VLAN database is
ignored (cleared), and the VTP and VLAN configurations in the startup configuration file are used. The
VLAN database revision number remains unchanged in the VLAN database.
• If the VTP mode or domain name in the startup configuration do not match the VLAN database, the
domain name and VTP mode and configuration for VLAN IDs 1 to 1005 use the VLAN database
information.
Related Topics
Configuring VTP on a Per-Port Basis , on page 2100
Configuring a VTP Version 3 Primary Server , on page 2097
Domain Names for Configuring VTP
When configuring VTP for the first time, you must always assign a domain name. You must configure all
switches in the VTP domain with the same domain name. Switches in VTP transparent mode do not exchange
VTP messages with other switches, and you do not need to configure a VTP domain name for them.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
2090
Information About VTP