spanning-tree forward time configuration

Unanswered Question
Feb 17th, 2008

Dear Pros,

if we need to configure the spanning-tree forward-time in the 4 switches network, this can be configured on single switch or all the switches.

swami

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
massimiliano.se... Sun, 02/17/2008 - 01:52

Hi,

You may configure all time parameters (hello time, max age and forward delay) on root switch only.

I hope this helps.

Best regards.

Massimiliano.

arumugasamy Sun, 02/17/2008 - 03:01

If i see the show spanning-tree vlan x detail

in the other non-root switches, the timer is not changed for those switches except the root switch.

SWAMI

massimiliano.se... Sun, 02/17/2008 - 04:08

Hi,

The timers are carried inside BPDU from root switch.

The local timers, in other switches except the root switch, are not changed.

In the show spanning tree, timers change only regarding BPDU relayed by the root switch.

The entire topology follows timers configured on the root switch.

I hope this helps.

Best regards.

Massimiliano.

Istvan_Rabai Sun, 02/17/2008 - 08:59

Hi,

Massimiliano is right.

When the STP topology is stable, only the timers of the root switch are applied to keep the topology stable.

If the root switch fails and another switch takes over the role of the root, then the timers of the new switch will be used to keep the STP topology stable.

From that point of view, it is best to configure the timers of at least 2 switches: the primary root switch and the secondary root switch, if it is necessary to change the default timer values at all.

Cheers:

Istvan

sakthivadivelv@... Tue, 02/19/2008 - 04:08

you meant to say that , need to configure it on root primary and secondary.

If the question says in the certification ..configure it on switch or switches..what is the right answer to reach the right answer?

Istvan_Rabai Tue, 02/19/2008 - 12:36

Hi Sakhti,

The right answer is dependent on the specific conditions of the specific exam question.

It is not possible to give you an answer in connection with specific exam questions, because I signed a non-disclosure agreement with Cisco.

It is possible to help you solve specific problems related to a configuration, or give you general guidelines on how to prepare for the exam, etc.

Cheers:

Istvan

Actions

This Discussion