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Is VLAN Trunking Protocol enabled or disabled by default on all switches ?

I have VTP Domain name showing nothing in command "" show VTP status ""

therfore does this mean VTP is disabled by default on all switches.

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    What kind of switches? Nexus switches don't have the vtp feature enabled by default.
    – cpt_fink
    Sep 15, 2015 at 5:08
  • cisco 2960 switches Sep 15, 2015 at 8:34

1 Answer 1

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Set vtp mode transparent to disable VTP on a switch. If VTP version 2 is used, a transparent switch will still forward VTP advertisements, but, in any VTP version, the transparent switch will itself ignore VTP.

The VTP domain name and password must match between switches for VTP to work, and blank (null) VTP domain names and passwords are valid, so any switches set this way will exchange and use VTP advertisements.

VTP only travels on trunks. You can connect switches with access ports but VTP will not propagate across these ports.

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  • If I change the VTP domain name on server will it be automatically change in all client switches also. Sep 14, 2015 at 21:09
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    No. You need to set each switch to the domain and password. This is so you can create multiple domains. The switches read the advertisements, and they will ignore any advertisement that doesn't match the domain name and password which would be different from the server if you change the server.
    – Ron Maupin
    Sep 14, 2015 at 21:18
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    The current recommendation from Cisco is to disable VTP (transparent) in favor of manually restricting VLAN on the trunk. VTP, like so many layer-2 protocols can be a security problem. It also fits with Cisco's philosophy of one switch per VLAN to eliminate spanning-tree problems.
    – Ron Maupin
    Sep 14, 2015 at 21:23
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    To expand on the last comment, Cisco seems to be pushing a model where access switches are uplinked via SVI's and routing protocols are used instead of STP to manage redundant and failover links, since routing protocols (or at least EIGRP) converge faster than STP. Sep 15, 2015 at 12:27
  • EIGRP and OSPF both converge an order of magnitude faster than even RSTP.
    – Ron Maupin
    Sep 15, 2015 at 14:51

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