STP Convergence Mechanisms – Part 2

uplink-fast-example

STP Convergence Mechanisms – Part 2

Now, let’s continue with other STP COnvergence Mechanisms.

Loop Guard

Loop Guard is the STP mechanims that is used to protect the network against the layer 2 loops.

For example a switch can send BPDU but can not receive any BPDU from the other switch. And this is detected by UDLD. If the Loop Guard is configured, Loop Guard puts the port in “Loop Inconsistence State” instead of going through Forwarding state in this situation. But if there is no Loop Guard, then, the port continue to sends BPDU and goes through Forwarding State. In such a situation, a Layer 2 Loop occurs. Loop Guard is mainly used to avoid such cases.


loop-guard-example

To configure Loop Guard globally on a Cisco switch, you can use “spanning-tree loopguard default” command. Beside, to enable Loop Guard on a specific interface, you can use “spanning-tree guard loop” command.

Uplink Fast

Uplink Fast is the convergence accelerator mechanims that can be configured on only Access switches and on the uplink ports. With Uplink Fast mechanims, if a port fails, then the second way on the uplink become active imediately. This immediate access, reduces the convergence time.


uplink-fast-example

We're Sorry!

Full Access is for only IPCisco Crew...

With IPCisco Membership, You Can Access:

• All Certification Courses (Cisco, Juniper, Nokia and Huawei),
• Thousands of Questions (Lesson Quizes and Special Quiz Section),
• Carieer Consultancy, CV/Resume Check, Career Advice Meeting,
• Cheat Sheets, Job Interview Trainings, Network Tools,
You will be Member of a Big IPCisco Community,
You will Learn Network Lessons with Always,
New And Different Learning Styles!
We are waiting for you!

STP Convergence Mechanisms

STP Convergence Mechanisms – Part 1
STP Convergence Mechanisms – Part 2

Leave a Reply