Verifies the VLAN removal.
Aug 22, Report Inappropriate Content. PM. PM. Hi Ahmed, The above command should remove only VLAN from the configuration (see below): LAB (config)#do sh run i span spanning-tree mode pvst spanning-tree extend system-id spanning-tree vlan, priority LAB (config)#Z LAB#sh Aug 23 %SYSCONFIG_I: Configured from console by console LAB#sh span root Root Hello Max Fwd Vlan Estimated Reading Time: 1 min. Sep 22, To reduce the number of active spanning-tree instances, you have a several options: If your switches are all Cisco and running in VTP server or client mode, then you can enable VLAN pruning on the VTP server (s) with the vtp pruning command.
This will prune unnecessary VLANs from your trunk links automatically.
The reasoning is that an attacker is unable to compromise a root bridge if there is no spanning-tree.
Put simply, the spanning tree protocol, or STP, is designed to remove loops from a network with minimal intervention by a network operator. Tree fell on man does this by electing one bridge in the network as the root of a “tree” that branches from the root, creating acycluc paths to every other bridge. Where two or more links in the network could cause a loop, traffic is blocked from traversing one of the links.
There are several spanning-tree tools at our disposal: BPDUGuard shuts down a port if it receives a BPDU. Enable this on any port where BPDU’s are not expected, such as client facing ports.
BPDUFilter ignores any BPDUs seen on a port. This disables spanning-tree. While there may be some rare corner-cases where this is useful, it can be bushmulching.barted Reading Time: 7 mins. Open a CLI window on switch S3 and issue the command show spanning-tree vlan 1. Leave the CLI window open. Open configuration window b. Select the delete tool from the menu bar and click the cable that connects S1 and S2.
If you do show spanning-tree VLAN A from the access layer, you see that the root bridge is Agg1. If you type the same command for VLAN E on the same switch, you see that the root bridge is Agg2.
This difference occurs because VLAN A and VLAN E are mapped to two different bushmulching.bar Size: 1MB.