From: Bob Sinclair (bsin@cox.net)
Date: Thu Dec 18 2003 - 10:58:55 GMT-3
The STP timers are based on a diameter of 7. No two bridges should be more
than 7 hops away from each other. The diameter is not measured from the
root, which might better be termed a radius. The diameter limit of 7 is
based on the default timers and rather conservative assumptions. Here is a
link to a good discussion of the issues:
http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a00800951ac.shtml
-Bob Sinclair
CCIE #10427, CISSP, MCSE
www.netmasterclass.net
----- Original Message -----
From: "Mike Williams" <ccie2be@swbell.net>
To: <dcopleston@manfinancial.com>; <ccielab@groupstudy.com>
Sent: Thursday, December 18, 2003 8:18 AM
Subject: RE: Maximum spanning tree domain size
> Well, it's not so much the number of switches, as we have well over 100+
> switches all in one STP at one location. I think you're asking about
> the STP maximum diameter. Someone else here I'm sure can tell me if
> this is right or not, but I seem to recall that you want to keep your
> Spanning Tree diameter to 15 or less (no more than 15 layer 2 hops
> between any 2 end devices). From the sounds of it, you have all of your
> switches connected to one of two core switches (one of which I'm hoping
> you've made the spanning tree root) so your network diameter is no more
> than 3, so you should be fine.
>
> Mike W.
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> dcopleston@manfinancial.com
> Sent: Thursday, December 18, 2003 6:14 AM
> To: ccielab@groupstudy.com
> Subject: Maximum spanning tree domain size
>
>
> On a large layer 2 network with multiple campus wide VLANs what would
> people regard as the maximum number of switches that can stably be used?
> Has any one found any documentation stating any such limits. I am
> looking at a legacy LAN with over 40 switches in the same STP tree (all
> are radiating off 2 core devices in a non-meshed star topology).
>
> In order to help convince management that migrating this to a more
> modern multi-layer approach is the way forward I am looking for evidence
> showing the weakness of the current approach.
>
> Thanks,
> Daniel
>
>
> MAN FINANCIAL LIMITED E-MAIL DISCLAIMER
>
> "This electronic mail message was sent by Man Financial Limited ("MFL")
> of Sugar Quay, Lower Thames Street, London, EC3R 6DU, a Company
> registered in England no. 1600658. MFL is authorised and regulated by
> the Financial Services Authority in the UK and is a member of the Man
> Group. MFL appear on the UK Financial Services Authority register under
> no. 106052.
>
> This electronic mail message is intended only for the personal and
> confidential use of the designated recipient(s) named above. If you are
> not that person, you are not authorised to view, disseminate, distribute
> or copy this message or any part of it without our consent; and you are
> requested to return this message to the sender immediately and delete
> all copies from your system.
>
> The value of investments and foreign exchange can go up as well as down
> and involve the risk of loss. You may lose more than the amount
> originally invested and, in respect of products traded on margin, you
> may have to pay more later. Opinions, conclusions and other information
> expressed in this message are not given or endorsed by MFL unless
> otherwise indicated by an authorised representative.
>
> Due to the electronic nature of e-mails, there is a risk that the
> information contained in this message has been modified. Consequently
> MFL can accept no responsibility or liability as to the completeness or
> accuracy of the information.
>
> Whilst efforts are made to safeguard messages and attachments, MFL
> cannot guarantee that messages or attachments are virus free, do not
> contain malicious code or are compatible with your electronic systems
> and does not accept liability in respect of viruses, malicious code or
> any related problems that you may experience.
>
> MFL's e-mail system is for business purposes only. All e-mail may be
> reviewed by authorised personnel, and may be provided to regulatory
> authorities or others with a legal right to access such information.
>
> If you would like to find out more information about Man Financial
> Limited please click on the following hyperlink to our web site. "
>
> Web site: http://www.manfinancial.com
>
> _______________________________________________________________________
> Please help support GroupStudy by purchasing your study materials from:
> http://shop.groupstudy.com
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Please help support GroupStudy by purchasing your study materials from:
> http://shop.groupstudy.com
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Sat Jan 03 2004 - 08:25:42 GMT-3