Cool stuff .. Even i read these formules longg time back in one of switching books . But hardly I came across situations where we change them based on formula
I liked this discussion :) Gaurav On Wed, Apr 14, 2010 at 11:55 PM, Syed Zaidi <[email protected]> wrote: > Got it mate!! > If we use this formula it sets the timer according to the diameter value. > max age = (4 * hello) + (2 * diameter) – 2 forward delay = ((4 * hello) + (3 > * diameter)) / 2 > Basically what we know about max-age as 20 secs (21secs actual), is derived > by keeping the diameter value of 7, similarly we get the forward delay of > 15secs (14.5 secs actual) again based on the a diameter value of 7. > > Regards, > Syed > > On Wed, Apr 14, 2010 at 5:30 PM, Joe Astorino <[email protected]> > wrote: >> >> That is a great question. There is a formula for it that I do not recall >> but you should be able to find it. I will have a look as well when I have a >> second and let you know. >> >> Please do let the group know your findings as well >> >> Sent from my Verizon Wireless BlackBerry >> >> Regards, >> >> Joe Astorino - CCIE #24347 >> Sr. Technical Instructor - IPexpert >> Mailto: [email protected] >> Telephone: +1.810.326.1444 >> Live Assistance, Please visit: www.ipexpert.com/chat >> eFax: +1.810.454.0130 >> >> IPexpert is a premier provider of Self-Study Workbooks, Video on Demand, >> Audio Tools, Online Hardware Rental and Classroom Training for the Cisco >> CCIE (R&S, Voice, Security & Service Provider) certification(s) with >> training locations throughout the United States, Europe, South Asia and >> Australia. Be sure to visit our online communities at >> www.ipexpert.com/communities and our public website at www.ipexpert.com >> >> ________________________________ >> From: Syed Zaidi <[email protected]> >> Date: Wed, 14 Apr 2010 17:21:52 +0300 >> To: Joe Astorino<[email protected]> >> Cc: R&S OSL<[email protected]> >> Subject: Re: [OSL | CCIE_RS] Setting layer 2 network diameter.. >> Well said but how does it impact the timers, I mean based on what >> criteria? >> If I have five switches A,B,C, D & E, where A is the root and B & C are >> connected directly to it, whereas D is connected to B and E is connected to >> C, finally D & E has a connection between them. In such a scenario if we set >> the diameter to 3, how will the timers be readjusted for optimization? >> Regards, >> Syed >> >> On Wed, Apr 14, 2010 at 4:03 PM, Joe Astorino <[email protected]> >> wrote: >>> >>> Basically this knowledge can help you in the CCIE lab if you are asked >>> to do it : ) Other than that, in a lab as small as the CCIE lab this >>> feature is probably not going to make or break your network. As far >>> as if it is tested, it is part of spanning-tree so I would definitely >>> consider it fair game. The important thing to be aware of is that it >>> dynamically changes your STP timers as you quoted from the docCD. >>> >>> >>> >>> On Wed, Apr 14, 2010 at 8:58 AM, Syed Zaidi <[email protected]> wrote: >>> > This is an extract from Cisco configuration guide for Catalyst 3560.. >>> > how >>> > can setting L2 diameter help us in CCIE lab? Are the candidate tested >>> > on >>> > this in relation to reducing convergence timers? >>> > Use the diameter keyword to specify the Layer 2 network diameter (that >>> > is, >>> > the maximum number of switch hops between any two end stations in the >>> > Layer 2 network). When you specify the network diameter, the switch >>> > automatically sets an optimal hello time, forward-delay time, and >>> > maximum-age time for a network of that diameter, which can >>> > significantly >>> > reduce the convergence time. You can use the hello keyword to override >>> > the >>> > automatically calculated hello time. >>> > Regards, >>> > Syed >>> >_______________________________________________ >>> > For more information regarding industry leading CCIE Lab training, >>> > please >>> > visit www.ipexpert.com >>> > >>> > >>> >>> >>> >>> -- >>> Regards, >>> >>> >>> >>> Joe Astorino - CCIE #24347 >>> Sr. Technical Instructor - IPexpert >>> Mailto: [email protected] >>> Telephone: +1.810.326.1444 >>> Live Assistance, Please visit: www.ipexpert.com/chat >>> eFax: +1.810.454.0130 >>> >>> IPexpert is a premier provider of Self-Study Workbooks, Video on >>> Demand, Audio Tools, Online Hardware Rental and Classroom Training for >>> the Cisco CCIE (R&S, Voice, Security & Service Provider) >>> certification(s) with training locations throughout the United States, >>> Europe, South Asia and Australia. Be sure to visit our online >>> communities at www.ipexpert.com/communities and our public website at >>> www.ipexpert.com >> > > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
