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10 Words or Less – Spanning Tree

413 Words. Plan about 2 minute(s) to read this.

3560 IOS 12.2(25)SEE Commands for Spanning Tree

show spanning-tree – display large variety of STP information

spanning-tree backbonefast – root or blocked port listens immediately when inferior BPDU received

spanning-tree bpdufilter – port won’t send or receive BPDUs; can cause topology loops

spanning-tree bpduguard – err-disable port upon receipt of a BPDU

spanning-tree cost – set interface port cost where higher value equals more cost

spanning-tree etherchannel guard misconfig – err-disable ports when switch detects misconfigured etherchannel

spanning-tree extend system-id – use 802.1t STP extensions to extend system ID

spanning-tree guard loop – alternate/root ports won’t become designated because of unidirectional link

spanning-tree guard root – port becomes “root-inconsistent” if chosen as root port

spanning-tree link-type – override RSTP-detected state of point-to-point or shared

spanning-tree loopguard default – set loopguard globally for alternate/root ports

spanning-tree mode – set MST, PVST, or rapid-pvst

spanning-tree mst configuration – enter MST region config mode, set instance and more

spanning-tree mst cost – set interface port cost where higher value equals more cost

spanning-tree mst forward-time – tweak timers for listening and learning before port is forwarding

spanning-tree mst hello-time – interval between hello BPDUs sent by root switch; default=2

spanning-tree mst max-age – time without hello BPDUs heard, after which STP topology recomputes

spanning-tree mst max-hops – number of region hops before BPDU is discarded; default=20

spanning-tree mst port-priority – lower number = higher port priority; 0-240 by 16’s; default=128

spanning-tree mst pre-standard – send MSTP BPDUs in the old, pre-standard format only

spanning-tree mst priority – lower number = higher bridge priority; 0-61440 by 4096’s; default=32768

spanning-tree mst root – force bridge to become root primary (24576) or secondary (28672)

spanning-tree port-priority – lower number = higher port priority; 0-240 by 16’s; default=128

spanning-tree portfast (global configuration) – enable portfast on non-trunks or bpduguard/bpdufilter for portfast ports

spanning-tree portfast (interface configuration) – port immediately transitions from blocking to forwarding, skipping other states

spanning-tree portfast trunk – enable portfast on a trunk interface

spanning-tree transmit hold-count – BPDUs sent per second for RSTP/MSTP switches; default=6

spanning-tree uplinkfast – access switches immediately choose a new root port

spanning-tree vlan forward-time – listening/learning timers before port is forwarding; 4-30; default=15

spanning-tree vlan hello-time – root switch hello BPDU interval; 1-10; default=2

spanning-tree vlan max-age – recompute STP topology if no root BPDU; 6-40; default=20

spanning-tree vlan priority – lower number = higher bridge priority; 0-61440 by 4096’s; default=32768

spanning-tree vlan root – force bridge to become root primary (24576) or secondary (28672)