October 2008 Archives

Thanks to JW for this one...

The bigger and bigger your configuration grows, the longer you have to wait for a "show run" output. This is because each time the show run command is executed, the router queries each interface to find the individual commands entered. To save you some wait time, Cisco introduced a command to cache your configuration in memory (for a measly 15K memory sacrifice):

Router(config)#parser config cache interface

Reduced the "show run" time on my 3640 router from 8 seconds down to 3. Nice! Keep in mind that you must execute the "show run" command once after issuing this in order to cache the configuration.

If you're interested, here's all the info:

http://www.cisco.com/en/US/docs/ios/12_3t/12_3t7/feature/guide/gtinvgen.html

It looks like Cisco has now come up with an official CCIE training. It's a 6-month program through a Cisco Learning partner that uses a "blended" lab/e-learning/mentoring solution. Businesses who sponsor CCIE students will now have a way to check up on them (accountability for their studies). Sounds interesting! It's nice to see a "Cisco official" study path for the CCIE rather than just all the CCIE bootcamp processes.

Here's the scoop: https://cisco.hosted.jivesoftware.com/community/learning_center/cisco_360/

Don't ya love it when you attempt to Telnet or SSH from a Cisco device to an unreachable IP address? You're guaranteed wait time is 30 seconds...and there's no CTRL-SHIFT-6 breaking out of it. Here's a command-of-the day for you:

Router(config)#ip tcp synwait-time 5

This reduces the time the router waits for a reply SYN-ACK message to 5 seconds (from 30 seconds default) for all TCP sessions (including Telnet/SSH) coming from the router.

While I'm sure there could be an argument made that some networks may be delayed enough to have more than I five second delay from a SYN to a SYN-ACK...I'd say...fix your network.

Direct from the Cisco Wiki, a handy tip which allows you to show the complete configuration of Cisco devices without the breaks or pauses:

1. Type term len 0 in privileged mode to set your terminal to display without any breaks.
2. Type show run or show start to show the applicable config. The config will display without any breaks or pauses.

To display the config without lengthy certificate data, use show run brief.

This is useful for capturing the complete config for documentation purposes, especially if you do not have access via TFTP or the like.

Stumbled upon this SWEET analysis of the IPv4 Internet connectivity vs. the IPv6 Internet connectivity.

Wouldn't this be awesome on a nice poster-sized paper in the IT room?

-Thumbprint scanning
-Digital signatures
-Test forensics

The first two are obvious ways to prevent impostors from taking certification exams for you. However, this is nowhere NEAR as big of a problem as brain dumps / illegal "practice exams". This is the aim of the test forensics...but what does THAT mean? How can a certification exam tell if you're cheating?

Last month, Network World magazine posted a great article on the subject...and I quote:

The metrics (test forensics) reveal statistics such as how long it took the student to answer each test item, which answers were changed during the test, and how much time the student needed to complete the test. These metrics are compared with a historical baseline value, and too much variation raises a red flag. Before the student even walks out the door of the test center, the test results can be called into question, triggering further investigation.

Interesting...of course, I'm sure all the thoughts immediately go to the "false positive" world of real canidates being flagged incorrectly...but I would think these candidates would have nothing to fear anyway (they could handle an oral interview, or whatever follow-up there was)...What do you think?

PS - Vue said that 2008 would be a huge year for implementing these new security measures, but I have yet to thumbprint-scan or digitally sign for any exams...has anyone seen these new security measures???

I just went to register to take the CCNA Security exam...it looks like all the CCNA specialty exams are $250.00! I just took the CCNA Voice a couple months ago and it was $150.00... I'm hoping this is a mistake...

UPDATE: Called and spoke with both VUE and Cisco Certification support folks...it's not a typo - the CCNA Specialty Exams are all $250.00/attempt. Ouch. Apparently, the CCNA Voice exam I took earlier was a "pre-release" version & price.