8 Replies Latest reply: Sep 16, 2010 1:21 PM by leo RSS

    What troubleshooting scenarios would you recommend?

    lohaver

      The new v4.0 version of the CCIE lab exam uses a new approach to validate hands-on troubleshooting skills.  Some CCIEs may remember when the R&S lab exam was two days long and included a form of troubleshooting.  Before the second day, the exam proctor would "break" elements of the configuration candidates built on the first day to see if candidates could find and correct them.  This testing approach was eventually dropped because candidates were easily able to find faults in their "own" configurations and the approach did not prove predictive of actual expert level troubleshooting skills.

       

      The new design presents candidates with multiple preconfigured networks and requires them to diagnose and resolve the faults.  The presentation is similar to the way trouble tickets are used.  The CCIE exam team worked closely with Cisco support engineers to develop scenarios common in enterprise networks.  New scenarios will be introduced over time to keep the exam fresh.

       

      What types of troubleshooting scenarios would you recommend to our test designers?  Which faults tend to trip up the less skilled network engineers?  Let us know what you think.

        • 1. Re: What troubleshooting scenarios would you recommend?
          uraymo

          hmmm, duplex issues.

           

          Wrong IP addresses, incorrect network masks, Incorrect wild card masks.

           

           

           

           

          Also, I have noticed that junior engineers have trouble coloring in the network diagrams in a manner that really adds value to the diagram without clutering it.  So, if we had an excercise where we could color a diagram with virtual paint (crayons) then we could really show our skills off.

           

          Yeah these are all really tricky and should be on the exam.

           

           

          • 2. Re: What troubleshooting scenarios would you recommend?
            Scott Morris - CCDE/4xCCIE/2xJNCIE

            It's more fun when you hard code line speed on a 3560 and it turns off the AutoMDIX.    (you may need to change cabling types used on the switches for this to have any real effect)

             

            But all in all, lots of things can trip up junior admins as the network gets larger and more complicated.

             

            Scott

            • 3. Re: What troubleshooting scenarios would you recommend?
              Conwyn

              Hi Lora O

               

              I do not know which of this would be covered by CCIE but here are some real ones.

               

              maximium of routes in VRF - always fun when a node comes back again.

               

              Running spanning tree with HSRP -  guess the direction with two routers and two switches

               

              Change the config register so it picks up on the on-board flash and ignores the boot statement.

               

              CCIE voice -  switch off  ip routing for one way conversation.

               

              Let the 3750 switch nullify the precedence and watch Video Conference break up.

               

              Distribute bgp into rip and then rip into bgp with transparent metric

               

              Run gre over isdn dialler but do not change the mtu

               

              Switch off password encryption when using PPP CHAP but paste the user password into the configuration encrypted

               

              Missing dialer pool

               

              European one but  only provide less than 15 channels on a ISDN-PRI and try outbound call.

               

              E1 un-framed at one end and channelised the other.

               

              Voice Router clock source and slips

               

              Remove  BGP as-override when AS is same at both end. 

               

              Miscode the remote AS number and wait for the message. Also duplicate bgp router id

               

              Nat local devices before nating them onto  the Internet. Fun with Cisco phones and XML servers.

               

              delete tftp-server statements used to load Cisco phone and play tftp debug to guess which ones are missing.

               

              Translation patterns on CME when Telco has special rules. Play find the rules when a call fails.

               

              Anything involving default routes when they point in different directions.

               

              Fatigue test - keep person awake for 24 hours before testing to test the clarity of mind.

               

              Anything to do with using BGP to connect IS-IS AS

               

              NTP master and sync

               

              Violate the weight rule on a 7206

               

              HWIC-1FE on the wrong IOS

               

              Regards Conwyn

              • 4. Re: What troubleshooting scenarios would you recommend?
                uraymo

                I am still going to hope they add crayons and a coloring book. (yes I was being sarcastic/silly with my list of easy faults)

                 

                Seriously, your list is very good. Going to save that list for some fun experiments.

                 

                Take care.

                • 5. Re: What troubleshooting scenarios would you recommend?
                  Erick

                  Hi Conwyn.

                   

                  Remind me to never get on your bad side.

                   

                  "Switch off password encryption when using PPP CHAP but paste the user password into the configuration encrypted"

                  "Fatigue test - keep person awake for 24 hours before testing to test the clarity of mind."

                   

                  Erick

                  • 6. Re: What troubleshooting scenarios would you recommend?
                    Conwyn

                    Hi Uraymo

                     

                    Maybe using the aux port to provide PPP to access GUI and then change the modem type so the modcap statements no longer work.

                     

                    Guessing the E3 problem when the Telco box has no text above them. The classical local remote alarm scenario

                     

                    Show environment and broken power.

                     

                    Good old old one time password and aaa new-model with no user. Always good for a laugh.

                     

                    time acl and QOS

                     

                    Anything to do with dns-servers on the router.

                     

                    Regards Conwyn

                    • 7. Re: What troubleshooting scenarios would you recommend?
                      Conwyn

                      Hi Erick

                       

                      Perhaps instructing end-user to connect the correct cables.

                       

                      I think they should  be forced to roll out 100 Cisco telephones and then name the various cdp record types or explain OSPF network types.

                       

                      Interesting I had never seen the CDP record types listed until I read Cisco Telepresence Fundimentals. I have not quite read it all I am still stuck in the chapter about paint.

                       

                      I like Uraymo's idea. They could be given a network diagram from 1966 and using cdp guess what bits have changed.

                       

                      Regards Conwyn

                      • 8. Re: What troubleshooting scenarios would you recommend?
                        leo

                        I believe the troubleshooting section is great and hope it can be expanded. There should be an element of uncertainty in order to distinguish between the candidates who learned the technology and those who memorized the configuration. One question troubles me that I hesitate to ask in fear of being accused being paranoid. Are troubleshooting questions the same across all R&S exam locations? I got a sense that some people walk into the lab exam knowing what question they will receive. That could only be possible if someone who took the exam say in Beijing sends the information to a person taking the exam say in San Jose. (Beijing is 14 hours ahead of San Jose, so there is plenty of time to transfer the information after the exam). I am certain someone at Cisco looked at this possibility? Did they?