Solved

Enabling Spanning Tree Protokol on rest network with looped master switches

Posted on 2007-03-24
6
418 Views
Last Modified: 2008-01-09
Hi,

our network has about 30 switches. Our "master" switches are two HP 5308xl  linked together. These are linked with another 6 switches . This makes a loop on our network. All these switches have enabled STP.
Now I want to enable STP on other switches. My question is, if this can make nework problems or collisions. I dont know who is Routbridge of them and if changing of Routbrindge can be a problem.
0
Comment
Question by:MiamiCo
  • 3
  • 2
6 Comments
 
LVL 50

Accepted Solution

by:
Don Johnston earned 500 total points
ID: 18786061
Changing the switch that is the root bridge can cause a topology change which will affect the path that traffic takes to it's destination. It can also cause the network to re-converge creating a period of time (usually no more than 30 seconds) where no traffic is moving.

Common practice is to define the root bridge and alternate root bridge to be the switches closest to the common destinations of traffic. This is done by lowering the bridge priority to a value lower than the default of 32786 (0x800).

If you want to add a switch but don't want to learn the spanning tree topology of the existing network, you could raise the bridge priority of the new switches to a value greater than 32768. This should insure that the new switch will not take over as the root bridge.

That said, adding, removing switches (or link between switches) when the spanning tree topology is not know can be... exciting.  
0
 
LVL 17

Expert Comment

by:jburgaard
ID: 18786717
If you use defaults on 5308xl then the protocol you use is RSTP (R as in rapid) and the default is a priority of 8, whitch is a index number equivalent to 32786.
If you have more sw's with same given (or default) lowest priority, then the election of rootswitch is won by the sw. with the lowest priority AND lovest MAC-adress combination.

The command
show span
on each sw. can show the details in your existing network.

I think you should carefully plan for a root-switch and a backup-root.
0
 
LVL 3

Author Comment

by:MiamiCo
ID: 18789332
Thanks for answers. I think I should first "know" our spanning tree topology and then plan root and backup switch.
0
Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

 
LVL 50

Expert Comment

by:Don Johnston
ID: 20366019
Did you require any additional information beyond what I have already provided?
0
 
LVL 3

Author Comment

by:MiamiCo
ID: 20368126
No thanks. STP its runnig.  
My experience...  changing STP settings on one of our HP 2524 switches caused failure of this switch (i dont know why).
0
 
LVL 50

Expert Comment

by:Don Johnston
ID: 20368231
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

The following recovery method will work on All Cisco Switchs that run ISO software. You will need a good copy of the IOS version you want you use saved on your PC and a Com's Cable. The software for these switches comes as a .tar file. Tar is …
In this tutorial I will show you with short command examples how to obtain a packet footprint of all traffic flowing thru your Juniper device running ScreenOS. I do not know the exact firmware requirement, but I think the fprofile command is availab…
This Micro Tutorial will teach you how to censor certain areas of your screen. The example in this video will show a little boy's face being blurred. This will be demonstrated using Adobe Premiere Pro CS6.
Email security requires an ever evolving service that stays up to date with counter-evolving threats. The Email Laundry perform Research and Development to ensure their email security service evolves faster than cyber criminals. We apply our Threat…

823 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