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spanning tree root guard apply to all vlans or individual vlan?

When the switch with spanning tree root guard deteces its neighbor switch become the root for one of the vlans, will it block the whole port or just the vlan only?

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Re: spanning tree root guard apply to all vlans or individual vl

When you enable root guard on a per-port basis, it is automatically applied to all of the active VLANs to which that port belongs. When you disable root guard, it is disabled for the specified port(s). If a port goes into the root-inconsistent state, it will automatically go into the listening state.

Root guard enabled on an interface applies to all the VLANs to which the interface belongs. Do not enable the root guard on interfaces to be used by the UplinkFast feature. With UplinkFast, the backup interfaces (in the blocked state) replace the root port in the case of a failure. However, if root guard is also enabled, all the backup interfaces used by the UplinkFast feature are placed in the root-inconsistent state (blocked) and are prevented from reaching the forwarding state.

http://www.cisco.com/en/US/products/hw/switches/ps5023/products_configuration_guide_chapter09186a008017ed40.html#1032250

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