You are correct about the distance command. We'll update the solution. Thanks for reporting this.
-- Marko Milivojevic - CCIE #18427 Senior Technical Instructor - IPexpert FREE CCIE training: http://bit.ly/vLecture Mailto: [email protected] Telephone: +1.810.326.1444 Web: http://www.ipexpert.com/ On Mon, Sep 20, 2010 at 19:29, Bojan Zivancevic <[email protected]> wrote: > Well, you are technically right about the wildcard/mask thing. DSG way it > would be valid for any neighbor. But I doubt this would help me on the exam. > :) It seems we have to have almost mind-reading capabilities in order to > type the commands expected. > > > > Thanks for the clarification about the distance... > > > > Best Regards, > > > > Bojan Zivancevic > > Network Engineer > > > > From: Tyson Scott [mailto:[email protected]] > Sent: Monday, September 20, 2010 19:25 > To: Bojan Zivancevic; 'CCIE_RS OnlineStudyList' > Subject: RE: [OSL | CCIE_RS] vol.1 task 8.13 problem (route poisoning) > > > > Well I would say your answer is more accurate but the answer in the book is > still OK. > > > > As Cisco will hold the route in the table until it confirms the other route > is stable and more preferred what you are seeing is the expected behavior. > You are not getting another route to replace it or it would remove it on the > second update and only hold the old one in the RIP database until it > expires. > > > > Regards, > > > > Tyson Scott - CCIE #13513 R&S, Security, and SP > > Managing Partner / Sr. Instructor - IPexpert, Inc. > > Mailto: [email protected] > > Telephone: +1.810.326.1444, ext. 208 > > 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: [email protected] > [mailto:[email protected]] On Behalf Of Bojan Zivancevic > Sent: Monday, September 20, 2010 12:34 PM > To: 'CCIE_RS OnlineStudyList' > Subject: [OSL | CCIE_RS] vol.1 task 8.13 problem (route poisoning) > > > > First, I think there is an error in DSG. Second, I stumbled into an > interesting behavior of the “distance” command. > > > > This is a task about RIP route poisoning. We can go for offset-list method > or distance one. The WB goes for distance, ok. > > > > DSG says that we should enter “distance 255 150.100.12.2 255.255.255.255 1” > which IMHO is wrong. The context help and command reference agree that we > should enter wilcard there, and not the subnet mask. So, it should be > “150.100.12.2 0.0.0.0”. > > > > That can be confirmed with “sh run | i distance” which then show that the > router automatically converted the distance command into “distance 255 > 0.0.0.0 255.255.255.255 1” because of the “ANY” wildcard used. > > > > So, I think it is definite that we should use wildcard. Anyway, I tried it > this way and it worked. But... > > > > Now, about the second part of my email. I would really love somebody to > explain why is this happening. > > > > When I corrected the “distance” command, I noticed that the update timer has > not been reset anymore. The route just slowly started to dissapear. That > confused me and I thought all this is not working. That is why I changed the > distance to “254” in order to be able to see the route in the table even > after the command. All other routes behaved normal, just this one. So, i > chose to wait and saw that the distance command did have the effect, but > only after the flush timer has expired, the route got deleted from the > table, and another RIP update came after that. Only then the AD got changed > to 254... Why the router is not changing the distance immediately after the > next RIP update? Why the flush timer and all? > > > > See for yourself: > > > > R1(config-router)#do sho access-l 1 > > Standard IP access list 1 > > 10 permit 200.0.0.9 (75 matches) > > R1(config-router)#do sh run | i dista > > distance 254 150.100.12.2 0.0.0.0 1 > > > > .... and we still have the old “120” distance... > > R1(config-router)#do sro 200.0.0.9 > > Routing entry for 200.0.0.9/32 > > Known via "rip", distance 120, metric 3 > > Redistributing via rip > > Last update from 150.100.12.2 on FastEthernet0/0, 00:00:28 ago > > ..... time is passing... > > R1(config-router)#do sro 200.0.0.9 > > Routing entry for 200.0.0.9/32 > > Known via "rip", distance 120, metric 3 > > Redistributing via rip > > Last update from 150.100.12.2 on FastEthernet0/0, 00:02:54 ago > > ... some more... > > R1(config-router)#do sro 200.0.0.9 > > Routing entry for 200.0.0.9/32 > > Known via "rip", distance 120, metric 4294967295 (inaccessible) > > Redistributing via rip > > Last update from 150.100.12.2 on FastEthernet0/0, 00:04:01 ago > > .... and here it is, the new AD... > > R1(config-router)#do sro 200.0.0.9 > > Routing entry for 200.0.0.9/32 > > Known via "rip", distance 254, metric 3 > > Redistributing via rip > > Last update from 150.100.12.2 on FastEthernet0/0, 00:00:20 ago > > > > > > Best Regards, > > > > Bojan Zivancevic > > Network Engineer > > _______________________________________________ > 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
