From: Gary Duncanson (gary.duncanson@googlemail.com)
Date: Wed Oct 17 2007 - 10:38:40 ART
Makes sense.
Use it on access switches and the like.
----- Original Message -----
From: "Scott Morris" <smorris@ipexpert.com>
To: "'Simon Grace'" <SimonG@pcsystems.gr>; "'Joseph Brunner'"
<joe@affirmedsystems.com>; <hadek.el-ayachi@nsn.com>;
<ccielab@groupstudy.com>
Sent: Wednesday, October 17, 2007 2:12 PM
Subject: RE: IE lab40
> Portfast. :)
>
> -----Original Message-----
> From: Simon Grace [mailto:SimonG@pcsystems.gr]
> Sent: Wednesday, October 17, 2007 3:39 AM
> To: Joseph Brunner; Scott Morris; hadek.el-ayachi@nsn.com;
> ccielab@groupstudy.com
> Subject: RE: IE lab40
>
> Whilst we are on the subject...
>
>
> Okay, forward-time can affect the speed in which port becomes active
> regarding spanning-tree
>
> This must be configured on the root switch...correct ?
> I've tried it on the secondary root and it ain't happening!
>
> You also have port-fast.
>
> Amongst the collective does anyone else know a way to decrease the time
> taken for a port to come up which is NOT configured on the root switch ?
> ? ?
>
> I'd be interested to hear your views.
>
> Simon.
>
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Joseph Brunner
> Sent: Tuesday, October 16, 2007 10:08 PM
> To: 'Scott Morris'; hadek.el-ayachi@nsn.com; ccielab@groupstudy.com
> Subject: RE: IE lab40
>
> Cleary Scott, this is only on ports that were previously blocked because
> of
> receipt of an inferior BPDU, correct? So you're specifically describing
> the
> max-age HOLD TIME used to block alternate root paths with 802.1d?
>
> I'm asking because if I...
>
> do fwd delay = 7 seconds on ports where users connect and they go from
> down
> to FWD in 14 seconds ONLY (this in lieu of portfast, etc). Notice no 20
> second delay...
>
> watch this test... (and pay attention to the log timestamps, 14 seconds
> from
> no shut -> FWD on a port which previously was not holding a bpdu for max
> age
>
>
> rack1sw1(config)#vlan 10
> rack1sw1(config-vlan)#exit
> rack1sw1(config)#sp
> rack1sw1(config)#spanning-tree vlan 10 for rack1sw1(config)#spanning-tree
> vlan 10 forward-time 7 rack1sw1(config)#int g0/1 rack1sw1(config-if)#sw
> rack1sw1(config-if)#switchport mode access rack1sw1(config-if)#sw
> rack1sw1(config-if)#switchport access vlan 10 rack1sw1(config-if)#int g0/1
> rack1sw1(config-if)#shut rack1sw1(config-if)#^Z rack1sw1#debug sp
> rack1sw1#debug spanning-tree event Spanning Tree event debugging is on
> rack1sw1#conf t Enter configuration commands, one per line. End with
> CNTL/Z.
> rack1sw1(config)#logg con
> rack1sw1(config)#int g0/1
> rack1sw1(config-if)#no shut
> rack1sw1(config-if)#^Z
> rack1sw1#
> *Mar 1 19:46:51: %SYS-5-CONFIG_I: Configured from console by console
> rack1sw1# *Mar 1 19:46:52: setting bridge id (which=3) prio 32778 prio
> cfg
> 32768 sysid 10 (on) id 800A.0015.2b2c.7e80 *Mar 1 19:46:52: set portid:
> VLAN0010 Gi0/1: new port id 8001 *Mar 1 19:46:52: STP: VLAN0010 Gi0/1 ->
> listening rack1sw1# *Mar 1 19:46:53: %LINK-3-UPDOWN: Interface
> GigabitEthernet0/1, changed state to up rack1sw1# *Mar 1 19:46:54:
> %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1,
> changed
> state to up rack1sw1# *Mar 1 19:46:59: STP: VLAN0010 Gi0/1 -> learning
> rack1sw1# *Mar 1 19:47:06: STP: VLAN0010 Gi0/1 -> forwarding
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> Scott Morris
> Sent: Tuesday, October 16, 2007 1:16 PM
> To: hadek.el-ayachi@nsn.com; ccielab@groupstudy.com
> Subject: RE: IE lab40
>
> Max age is how long you wait after receiving the last BPDU before
> recalculating things (like a dead timer).
>
> When a port comes up, you block for 20 seconds initially. (first plug
> in)
> That 20 seconds is not a changeable timer. Then you listen/learn for 15
> seconds each. That's the "normal" 50 seconds.
>
> If you want the whole thing to take 34 seconds, subtract 20 first.
> Since
> you can't change that. So now we have 14 seconds for listening and
> learning. These timers must be the same per spec, so divide by two (7)
> and
> that's your forward-timer.
>
> HTH,
>
>
> Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713,
> JNCIE-M
> #153, 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 16, 2007 11:39 AM
> To: ccielab@groupstudy.com
> Subject: IE lab40
>
> Hi experts,
> In Lab40, the question said: access ports should take 34 seconds to come
> online.
> I was expecting the answer: spanning-tree forward-time 17. I checked
> this
> answer using sh and no sh in one access port.
> However the answer is spanning-tree forward 7???????????????? It takes
> into
> consideration max-age:( Any comment please
>
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