a new examination…

i remember reading from numerous sources, quite some time ago, that when you’re troubleshooting, DO NOT rely on show run… experiencing brian mcgahan videos in the last few days and his expert handling of output to make clear determinations reminded me of this… show run shows you NOTHING… if you cannot intelligently examine output from sources other than the running-config, you are NOTHING…

years ago when i first started studying ccna i’d race through or glance over the output presented in the books… this is an enormous mistake… the output is everything, and your ability to dissect the output is THE difference…

in recent years i’ve noted that comments are now peppered through the output in books and at cisco.com… or maybe i just never noticed back then… this is a great advantage over the method of, “see diagram below” after explaining some points… you no longer have to bounce back and forth between the diagram and the explanation… for example:

R5# sh ip bgp | begin network
Network
*> 10.14.0.0/16
Next Hop
0.0.0.0
Metric LocPrf Weight Path
0
32768 i
! Finally, auto-summary is re-enabled (not shown in the example).
! 10.14.0.0/16 is still an exact match, so it is
! still injected. 10.0.0.0/8 is also injected because of the network 10.0.0.0 command.
R5# sh ip bgp | begin network
Network Next Hop * 10.0.0.0 0.0.0.0
Metric LocPrf Weight Path
0 32768 i
* 10.14.0.0/16 0.0.0.0 0 32768 i