Cisco CCNP BCMSN Assessment Tutorial Spanning Tree Protocol STP Timers 65322

Within your BCMSN / CCNP assessment research, it"s an easy task to ignore some of the details of Spanning Tree Protocol (STP). Discover more on our related article directory - Click here: remove frames. After all, you learned all of that in-your CCNA reports, right? Definitely not! While some of the BCMSN content is a evaluation for you, there are some facts regarding common subjects that you need to learn. Visit team to research the purpose of it. That includes the timers for STP - Hello Time, MaxAge, and Forward Delay.

You may possibly remember these timers from your own CCNA reports as well, and you should also remember that these timers shouldn"t be changed lightly. What you might not have recognized is that if you decide to change any and many of these timers, that change must be designed on-the root bridge! The root bridge can advise the nonroot turns of the change via BPDUs.

Hello Time could be the period between BPDUs, two seconds automatically.

Forward Delay may be the length of the hearing and learning STP levels, having a default value of 15 seconds.

Maximum Age, described from the switch as MaxAge, may be the amount of time a switch can keep a BPDU"s articles before losing it. The standard is 2-0 seconds.

The worthiness of those timers could be changed with the spanning-tree vlan command shown below. Verify the changes using the show spanning-tree command. Identify more on our affiliated use with by clicking open site in new window.

SW1( config )#spanning-tree vlan 1??

forward-time Set the forward delay for the spanning tree

hello-time Set the hello interval for your spanning tree

max-age Set the max age interval for the spanning tree

priority Set the bridge priority for the spanning tree

root Configure switch as root

SW1( config )#spanning-tree vlan 1 hello-time 5

SW1( config )#spanning-tree vlan 1 max-age 30

SW1( config )#spanning-tree vlan 1 forward-time 20

SW1( config )#^Z

SW1#show spanning-tree vlan 1

VLAN0001

Spanning tree enabled method ieee

Origin IDENTITY Priority 32769

Address 000f.90e1.c240

This bridge is the root

Hi Time 5 sec Max Age 30 sec Forward Delay 20 sec

Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)

Address 000f.90e1.c240

Hello Time 5 sec Max Age 30 sec Forward Delay 2-0 sec

Aging Time 300

Program Part Sts Charge Prio.Nbr Sort

---------------- ---- --- --------- -------- --------------------------------

Fa0/11 Desg FWD 1-9 128.11 P2p

Fa0/12 Desg FWD 19 128.12 P2p

Again, you need to always just take great care in changing these timers. These defaults are set for grounds - assisting to reduce switching loops!.