Spanning-Tree Vlan - Dell Networking 2024 Reference Manual

User Guidelines
DirectLink Rapid Convergence (DRC) can be configured even if the switch is
configured for MST(RSTP) mode. It only has an effect when the switch is
configured for STP-PV or RSTP-PV modes. Enabling DRC sets the switch
priority to 49152. Path costs less than 3000 have an additional 3000 added
when DRC is enabled. This reduces the probability that the switch will
become the root switch.
DRC immediately changes to an alternate root port on detecting a root port
failure and change the new root port directly to the fowarding state. A TCN is
sent for this event.
After a switchover to an alternate port (new root port), DRC multicasts a
gratuitous frame on the new root port on behalf of each attached machine so
that the rest of the network knows to use the secondary link to reach that
machine.
RSTP-PV embeds support for IRC and DRC. There is no provision to enable
or disable these features in RSTP-PV configured switches.
Example
console(config)#spanning-tree uplinkfast

spanning-tree vlan

Use the spanning-tree vlan command to enable per VLAN spanning tree on a
VLAN. Use the no form of the command to remove the VLAN as a separate
spanning tree instance.
Syntax
spanning-tree vlan {
no spanning-tree vlan {
vlan-list –A single VLAN ID or a list of VLAN IDs in comma delineated or
•
range format with no embedded blanks. Range 1-4094.
Default Configuration
By default, each configured VLAN is automatically associated with a per
VLAN spanning tree instance. If more than eight VLANs are configured, the
excess VLANs do not participate in per VLAN spanning tree.
vlan-list
}
vlan-list
}
Spanning Tree Commands
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