spanning tree question

Posted on 2012-09-09
Last Modified: 2012-09-11
Can one reflect some light on the following scenario:
A switch is connected to hub (fa0/1 to fa0/1) and working fine. If someone attaches another copper wire between fa0/2(sw) to fa0/2(hub), how would the situation change?

1. fa0/1 on sw would go in block
2. fa0/1 on hub would go in block
3. fa0/2 on sw would go in block
4. fa0/2 on hub would go in block

This is like a cisco cert exam question...
Question by:totaram
    LVL 50

    Assisted Solution

    by:Don Johnston
    Hubs don't support STP.

    So it would be #3 (fa0/2 on sw would go in block).

    The port with a higher STP port number of the switch would block. There's no requirement that the STP port numbering has to follow the physical port numbers. Although on every switch I've ever seen, the lower physical port numbers have a lower STP port number.
    LVL 17

    Accepted Solution

    Effectively, seen from the switch it is the same thing as connected fa0/1 directly to fa0/2 on the switch.

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    What Security Threats Are You Missing?

    Enhance your security with threat intelligence from the web. Get trending threat insights on hackers, exploits, and suspicious IP addresses delivered to your inbox with our free Cyber Daily.

    We recently endured a series of broadcast storms that caused our ISP to shut us down for brief periods of time. After going through a multitude of tests, we determined that the issue was related to Intel NIC drivers on some new HP desktop computers …
    Configuring network clients can be a chore, especially if there are a large number of them or a lot of itinerant users.  DHCP dynamically manages this process, much to the relief of users and administrators alike!
    After creating this article (, I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
    In this tutorial you'll learn about bandwidth monitoring with flows and packet sniffing with our network monitoring solution PRTG Network Monitor ( If you're interested in additional methods for monitoring bandwidt…

    759 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    9 Experts available now in Live!

    Get 1:1 Help Now