From: Gary Duncanson (gary.duncanson@googlemail.com)
Date: Tue Oct 30 2007 - 15:34:39 ART
Scott,
Has that feature of loop detection remained fairly constant during the
evolution of all the spanning-tree variants in recent years?
----- Original Message -----
From: "Scott Morris" <smorris@ipexpert.com>
To: <hadek.el-ayachi@nsn.com>; <gary.duncanson@googlemail.com>;
<scott_ccie_list@it-ag.com>
Cc: <ccielab@groupstudy.com>
Sent: Tuesday, October 30, 2007 5:33 PM
Subject: RE: Getting a por to be in forwarding state in 14 seconds ....
> Correct, and the determination of a potential loop is initially determined
> by the received bridge ID within a BPDU!
>
>
> Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713,
> JNCIE-M
> #153, JNCIS-ER, CISSP, et al.
> CCSI/JNCI-M/JNCI-ER
> VP - Technical Training - IPexpert, Inc.
> IPexpert Sr. Technical Instructor
>
> A Cisco Learning Partner - We Accept Learning Credits!
>
> smorris@ipexpert.com
>
> Telephone: +1.810.326.1444
> Fax: +1.810.454.0130
> http://www.ipexpert.com
>
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> hadek.el-ayachi@nsn.com
> Sent: Tuesday, October 30, 2007 8:33 AM
> To: hadek.el-ayachi@nsn.com; gary.duncanson@googlemail.com;
> scott_ccie_list@it-ag.com
> Cc: ccielab@groupstudy.com
> Subject: RE: Getting a por to be in forwarding state in 14 seconds ....
>
> In the document "Using PortFast and Other Commands to Fix Workstation
> Startup Connectivity Delays", it is stated that:
> "STP dictates that the port starts out blocking, and then immediately
> moves
> through the listening and learning phases. By default, the port spends
> approximately 15 seconds listening and 15 seconds learning.
> During the listening state, the switch tries to determine where the port
> fits in the spanning tree topology. The switch especially wants to know
> whether this port is part of a physical loop. If the port is part of a
> loop,
> the port can be chosen to go into blocking mode. The blocking mode means
> that the port does not send or receive user data in order to eliminate
> loops. If the port is not part of a loop, the port proceeds to the
> learning
> state, in which the port learns which MAC addresses live off this port.
> This
> entire STP initialization process takes about 30 seconds.
> "
>
> This means that at startup, port start in bloking state and moves
> "immediately" to listning where he stays 15s, learning stay 15s and
> forwarding. This means that startup need 2*fwddelay.
>
> I made also some debugs in my switch using access and then trunk port:
> *Mar 2 01:39:27.438: set portid: VLAN0001 Fa0/1: new port id 8003 *Mar 2
> 01:39:27.438: Created spanning tree port Fa0/1 (2D3F560) for tree VLAN00
> 01 (2D3F8E0)
> *Mar 2 01:39:27.438: Enabling spanning tree port: FastEthernet0/1
> (2D3F560)
> *Mar 2 01:39:27.438: STP: VLAN0001 Fa0/1 -> listening *Mar 2
> 01:39:29.434:
> %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state t o up *Mar 2
> 01:39:29.434: Returning spanning tree port stats:
> FastEthernet0/1 (2D3F560)
> *Mar 2 01:39:29.434: Returning spanning tree port stats:
> FastEthernet0/1 (2D3F560)
> *Mar 2 01:39:29.434: Returning spanning tree port stats:
> FastEthernet0/1 (2D3F560)
> *Mar 2 01:39:30.441: %LINEPROTO-5-UPDOWN: Line protocol on Interface
> FastEthern et0/1, changed state to up *Mar 2 01:39:44.441: STP: VLAN0001
> Fa0/1 -> learning *Mar 2 01:39:49.634: Returning spanning tree port
> stats:
> FastEthernet0/1 (2D3F560)
> *Mar 2 01:39:49.634: Returning spanning tree port stats:
> FastEthernet0/4 (36D7430)
> *Mar 2 01:39:49.634: Returning spanning tree port stats:
> FastEthernet0/11 (3510988)
> *Mar 2 01:40:01.445: STP: VLAN0001 sent Topology Change Notice on
> Fa0/23
> *Mar 2 01:40:01.445: STP: VLAN0001 Fa0/1 -> forwarding
>
> Hence, port startup need 30 seconds.
>
> This is my understanding
>
>
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> ext
> ccielab-owner@groupstudy.com
> Sent: lundi 29 octobre 2007 15:44
> To: gary.duncanson@googlemail.com; scott_ccie_list@it-ag.com
> Cc: ccielab@groupstudy.com
> Subject: RE: Getting a por to be in forwarding state in 14 seconds ....
>
> It was my question and Scott Moriss s answer was that startup time is
> (maxage + 2*fwddelay) = 50s In your case, auusuming you are using STP (in
> RSTP where is no listing), you can use maxage= 10s and fwddelay = 2s Is it
> true Scott?
> thanks
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> ext
> Gary Duncanson
> Sent: samedi 27 octobre 2007 23:12
> To: Scott Vermillion
> Cc: ccielab@groupstudy.com
> Subject: Re: Getting a por to be in forwarding state in 14 seconds ....
>
> Hi Scott
>
> I have no idea how the archives work. I guess what Im saying is check
> about
> this recently. I think the 14 second thing on switches was covered by
> Scott
> Morris just a week or two ago.
>
> Regards
> Gary
>
> ----- Original Message -----
> From: "Scott Vermillion" <scott_ccie_list@it-ag.com>
> To: "'Gary Duncanson'" <gary.duncanson@googlemail.com>; "'ccie1101'"
> <ccie1101@gmail.com>
> Cc: <ccielab@groupstudy.com>
> Sent: Saturday, October 27, 2007 6:42 PM
> Subject: RE: Getting a por to be in forwarding state in 14 seconds ....
>
>
>> OK all, I have a question:
>>
>> How are you searching the archives?? Because when I try to search the
>
>> CCIE
>> list, the most recent results I get range anywhere from late 2004 to
> early
>> 2007! We used to have a very nice search function on the professional
>
>> board
>> but Paul had to disable it because it was apparently crashing the
> server.
>> But there must be something more effective than what I'm doing, which
> is
>> going here:
>>
>> http://www.groupstudy.com/cgi-bin/search
>>
>> So just as an example, I just plugged "Frame Relay" into the CCIE R&S
> list
>> and sorted by date in reverse order. The most recent result I get is
> a
>> post
>> on 3/07/2007. I suppose we've had one or two FR posts between now and
>
>> that
>> time, wouldn't you say? What am I doing wrong?
>>
>> Thx,
>>
>> Scott
>>
>>
>> -----Original Message-----
>> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
> Of
>> Gary
>> Duncanson
>> Sent: Saturday, October 27, 2007 4:06 AM
>> To: ccie1101
>> Cc: ccielab@groupstudy.com
>> Subject: Re: Getting a por to be in forwarding state in 14 seconds
> ....
>>
>> Check recent archives. I believe our friend Scott Morris covered this
> one.
>>
>> HTH
>>
>> Gary
>> ----- Original Message -----
>> From: "ccie1101" <ccie1101@gmail.com>
>> To: "Cisco certification" <ccielab@groupstudy.com>
>> Sent: Friday, October 26, 2007 6:18 PM
>> Subject: Re: Getting a por to be in forwarding state in 14 seconds
> ....
>>
>>
>>> GS,
>>> The question asks a total link startup delay of 14 seconds, at
> fist
>>> instance I just did the following,
>>> spanning-tree vlan 30 forward-time 14 but the TOTAL LINK delay is
> Hello +
>>> Forward Delay + Max Age.
>>>
>>> So therefore to get the port to be up in 14 seconds, would it be
> :-
>>> spanning-tree vlan 30 forward-delay 6 spanning-tee vlan 30 max-age 6
>>>
>>> and 2 seconds is for BPDU which gives us 14 seconds in total for
> the
>>> link to be up. Would this logic be
>>> correct ?
>>>
>>> Pls advice,
>>>
>>> ccie1101.
>>>
>>>
> _______________________________________________________________________
>>> Subscription information may be found at:
>>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Fri Nov 16 2007 - 13:11:19 ART