Re: 3 OSPF non-zero areas

"Towering genius disdains a beaten path. It seeks regions hitherto
unexplored." Abraham Lincoln

While Lincoln was not aware of the CCIE Lab Exam at the time, at least
one 2 point task in every lab exam seeks to find "towering
geniuses". :-)

Great idea for the list Jared. But sadly, our longest threads will
continue be about politics, race, and endless pontification regarding
extremely subjective non-technical topics. Although, it certainly does
add to the entertainment value of the list!

Warmest Regards,

Anthony J. Sequeira, CCIE #15626
Senior CCIE Instructor
http://www.InternetworkExpert.com

Internetwork Expert, Inc.
Toll Free: 877-224-8987
Outside US: 775-826-4344

Test your Core Knowledge today!
Q: Examine the output below. What is the purpose of the Punt Adjacency
in Cisco Express Forwarding?
A: The Punt Adjacency is used when a packet is not capable of being
handled by CEF on the Cisco device.
More Info: http://www.cisco.com/en/US/docs/ios/12_1/switch/configuration/guide/xcdcef.html

On May 6, 2009, at 2:38 PM, Jared Scrivener wrote:

> LOL. That's possibly the funniest (and unfortunately accurate) email
> I've
> read in a few days. I hope this isn't my last 2 cents...
>
> The thing I find most ironically hilarious is that almost everyone
> here is
> studying hard and paying hard earned cash for great materials from
> many of
> the instructors/vendors in this forum, yet these simple little
> challenges
> (which will probably teach everyone more in the space of one hour's
> difficult thought than they'd gain from reading a book or doing a
> complex
> lab for a day) don't gain much interest. I'll add that to my list of
> curious
> oddities...
>
> Cheers,
>
> Jared Scrivener CCIE3 #16983 (R&S, Security, SP), CISSP
> Sr. Technical Instructor - IPexpert, Inc.
> Telephone: +1.810.326.1444
> Fax: +1.810.454.0130
> Mailto: jscrivener_at_ipexpert.com
>
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf
> Of Tony
> Varriale
> Sent: Wednesday, 6 May 2009 11:24 AM
> To: 'Cisco certification'
> Subject: RE: 3 OSPF non-zero areas
>
> Usually what occurs at this point is the original poster realizes
> that a few
> people have chimed in and it's got all it's gonna get. Then, the
> original
> poster throws in their 2 cents and it goes into the archives.
>
> That's really how it worked in the old days.
>
> tv
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf
> Of
> Jared Scrivener
> Sent: Wednesday, May 06, 2009 12:01 PM
> To: smorris_at_internetworkexpert.com
> Cc: 'Anthony Sequeira'; 'Roy Waterman'; 'Anantha Subramanian
> Natarajan';
> 'Cisco certification'
> Subject: RE: 3 OSPF non-zero areas
>
> Thanks, Scott. One of my mentors once told me to "think like a
> router" and
> it was the best advice anyone ever gave me with respect to the CCIE.
>
>
>
> So, guys, I haven't seen any responses yet to my challenge question
> that
> didn't involve changing the question (I didn't say you could add any
> more
> tunnels). Back in the day (well, in the mid-late '90's when I was in
> high
> school and writing under my 31337 identity - the good old days) it was
> normal for highly technical engineers to post challenge questions to
> test
> each other - in my opinion that's one of the reasons that that the old
> "hackers" like Steve Wozniak got us to where we are now
> technologically.
>
>
>
> If I get some activity out of this I'd like us to consider doing more
> "thought experiments" here on the list - you'll be amazed how much
> better we
> all become. Oh, I didn't say that I'd get the answer right either -
> so don't
> be afraid to be wrong. J
>
>
>
> Cheers,
>
>
>
> Jared Scrivener CCIE3 #16983 (R&S, Security, SP), CISSP
>
> Sr. Technical Instructor - IPexpert, Inc.
>
> Telephone: +1.810.326.1444
>
> Fax: +1.810.454.0130
>
> Mailto: <mailto:jscrivener_at_ipexpert.com> jscrivener_at_ipexpert.com
>
>
>
> From: Scott Morris [mailto:smorris_at_internetworkexpert.com]
> Sent: Wednesday, 6 May 2009 3:49 AM
> To: Jared Scrivener
> Cc: Anthony Sequeira; Roy Waterman; Anantha Subramanian Natarajan;
> Cisco
> certification
> Subject: Re: 3 OSPF non-zero areas
>
>
>
> Jared's actually right on target with this method of thinking...
> As a cool
> way of studying (even though there's a plethora of variety between
> all the
> vendors!) a candidate should be able to take any existing scenario
> and start
> thinking about "what if....?".
>
> Never fear to create your own modifications to things, or even your
> own labs
> for that matter. For years, I've been telling people to work
> towards this.
> The cool thing (as seen below) is that you'll end up creating some
> REALLY
> ugly scenarios. But if you can think your way through them, you're
> doing
> great on your comfort level with the technology!
>
> Don't fear making mistakes! Every once and a while, you will create/
> dream
> an impossible scenario. Something that simply cannot happen. By
> the time
> you've worked at it, thought about it, labbed at it and tried to
> make it
> work, you have at least been spending time thinking about the
> protocol. No
> value is lost there.
>
> Any complicated task before you can be broken down into a series of
> simple
> tasks. That level of visualization though, requires a lot of
> work! :)
>
>
>
>
>
> Scott Morris, CCIEx4 (R&S/ISP-Dial/Security/Service Provider) #4713,
>
> JNCIE-M #153, JNCIS-ER, CISSP, et al.
>
> JNCI-M, JNCI-ER
>
> smorris_at_internetworkexpert.com
>
>
>
> Internetwork Expert, Inc.
>
> http://www.InternetworkExpert.com
>
> Toll Free: 877-224-8987
>
> Outside US: 775-826-4344
>
>
>
> Knowledge is power.
>
> Power corrupts.
>
> Study hard and be Eeeeviiiil......
>
>
>
>
> Jared Scrivener wrote:
>
> Every router has a connected route between them. Forget the numbered
> areas -
> Would the 3 contiguous GRE tunnels create a contiguous Area 0? I
> can't see
> why not. From there it follows that every other router's numbered area
> interfaces could be advertised into OSPF without incident (as if
> they were
> loopbacks). This won't force the control plane path via the data
> plane path
> to build the control plane path (my description of tunnel recursion)
> as the
> numbered OSPF areas are going to be learned via OSPF with a Tunnel
> interface
> next hop (which is fine) and the GRE packets that carry the OSPF
> packets
> will be routed via the connected routes as each GRE packet is going
> over a
> single hop to a directly connected neighbor.
>
> A more difficult question (here's a gauntlet thrown down) is what
> would
> happen if there was an area router in the middle of each area
> (between R1
> and R2, R2 and R3 etc)? Please don't lab this up and paste the
> configs until
> everyone has a chance to visualize and discuss this (explain your
> reasoning
> from first principles). It's a great thought experiment so pick an
> answer
> THEN prove it on hardware (if you can visualize this, you can do
> anything -
> this kind if puzzle is as hard as it gets).
>
> Game on. :)
>
> Cheers,
>
> Jared
>
> PS If you see three numbered areas and can't create area zero you can
> redistribute each area into the adjacent one other by putting them in
> separate processes (ASBRs and no ABRs). No need for tunnels (the least
> preferable method). Redistributing between multiple processes should
> be your
> second preferred method (VLs between routers and adding a loopback
> in Area 0
> is method number one of course, if allowed).
>
>
> On May 5, 2009, at 10:28 PM, Anthony Sequeira
> <mailto:asequeira_at_internetworkexpert.com> <asequeira_at_internetworkexpert.com
> >
> wrote:
>
>
>
>
> I think Anantha is really going "outside the box" here as he has NO
> area 0
> at all.
>
> It is really late for me, but I am thinking the only time we can go
> without
> an Area 0 in OSPF is when we only have a single area.
>
> Warmest Regards,
>
> Anthony J. Sequeira, CCIE #15626
> Senior CCIE Instructor
> http://www.InternetworkExpert.com
>
> Internetwork Expert, Inc.
> Toll Free: 877-224-8987
> Outside US: 775-826-4344
>
> Test your Core Knowledge today!
> Q: What is the BGP synchronization rule?
> A: This rule states that a router will not use or advertise a route
> learned
> by IBGP until a matching route has been learned from an IGP.
> More Info:
> www.cisco.com/en/US/docs/ios/12_2/ip/configuration/guide/1cfbgp.html#wp10029
> 10
>
> On May 6, 2009, at 1:01 AM, Roy Waterman wrote:
>
>
>
>
> Sorry what i meant to say was:
>
> You can create a virtual link to extend area 0 to area 4, and then
> create a
> 2nd virtual link to extend area 0 (which was extended to area 4) to
> area 5.
>
> 2009/5/6 Roy Waterman <mailto:roy.waterman_at_gmail.com>
> <roy.waterman_at_gmail.com>
>
>
>
>
> Hi Anantha
> You can create a virtual link to extend area 0 to area 4, and then
> create a
> 2nd virtual link to extend area4 to area 5.
>
>
> 2009/5/6 Anantha Subramanian Natarajan
> <mailto:anantha.natarajan_at_gravitant.com> <anantha.natarajan_at_gravitant.com
> >
>
> Hi All,
>
>
>
>
> Is it possible to run OSPF when there are three OSPF areas as shown
> below
> and none of them is not a area 0.
>
> R1 --ospf area3 --R2 ---ospf area4 ---R3 ----ospf area5 --R4
>
> My understanding is that, virtual-link would be only useful when to
> join a
> non-zero area to connect to area0 which is seperated by another
> non-zero area.Also the virtual links would be useful in case where
> area 0
> is
> broken in between a non-zero area.Assuming my above understanding is
> right,I
> am thinking the above scenario will not be able to use virtual links
> to
> propagate OSPF routes among R1,R2,R3,R4.
>
> In this case,if I would be able to build GRE tunnel between
> R1-R2,R2-R3,R3-R4 and run OSPF on area0 over them,In that case,will
> the
> OSPF
> routes would be able to get propagated ?
>
> Thanks for the help
>
> Regards
> Anantha Subramanian Natarajan
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
>
>
>
>
>
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
>
>
>
>
> --
> Regards
> Roy
>
>
>
>
> --
> Regards
> Roy
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
>
>
>
>
>
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
>
>
>
>
>
>
> Subscription information may be found
> at:http://www.groupstudy.com/list/CCIELab.html
>
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found
> at:http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Wed May 06 2009 - 15:15:01 ART