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Cisco Wireless Certifications Get a Refresh

Cisco recently updated their wireless exams to version 2.0 for both CCNA Wireless and CCNP Wireless.The new version brings a much needed update that is more in line with current Cisco wireless technologies.

Some of the updated content includes more recent versions of WLC and client software. They've also expanded 802.11n support and added more information about Video over wireless and Voice over wireless. Check Cisco's website for more details.

How to setup Configuration Change Notification and Tracking

Have you ever found yourself troubleshooting a problem caused by a coworker or consultant mistyping a command? It happens, everyone makes mistakes, but what's frustrating is when people won't own up and admit they made the mistake. Not only is it dishonest, it can impede a fast resolution by knowing what to undo.

As a result, you might find yourself wishing there was a relatively simple way to see every command typed into every router and switch in the network... You can do this with a AAA server, but it can be cumbersome to have to scour through the logs on your ACS server. However, there is another way and it's really easy to configure.

Configuration Change Notification and Logging, or simply Configuration Logging, is Cisco's method to log every configuration command entered on your Cisco IOS routers and switches. The feature was introduced in 12.3(4)T & 12.2(25)S, so it should be available in almost any IOS device that's been upgraded in the last 5 years. It can log locally up to a specified number of lines of config, and even send the commands off to a syslog server.

The following examples are from a Cisco 3550 switch and demonstrate how to configure and monitor change logging.

Google Proposing to make TCP Faster

Really interesting write-up, let's see if the world follows Google's advice (since that's what it will take!).

Violinist interrupted by Nokia ringtone

I've heard people say cell phones are rude. I say cell phones are merely a tool, it's the people that are rude. Give a rude person a cell phone, and they'll be rude with a cell phone.

During a live performance by Slovakian violinist Lukas Kmit, someone's Nokia went off. Instead of storming off the stage, Lukas made lite of it and mocked the ringtone. Check it out in this video..

SOPA Strike - January 18th

There is a strike planned for January 18th in protest of SOPA , the Stop Online Piracy Act, and PIPA, the Protect IP Act. If you find yourself going to sites like wikipedia or tucows on Wednesday, and they don't appear to work, this could be why.

Cisco Exam Prices Go Up...Again!

OUCH! In my email this morning:

"...The price changes are effective Monday, January 16, 2012.

  • CCNA exam 640-802 is increasing from $250 to $295 
  • CCDA exam 640-864 is increasing from $150 to $200 
  • ICND1 640-822 and ICND2 640-816 are increasing from $125 to $150"

Tekcert's 2nd Birthday!

Birthday Cake 2 is now 2 years old! Can you believe how fast the past year has gone? It was definitely a busy and productive year and hopefully 2012 will top it. I wanted to write this blog post mainly to celebrate's birthday, but I also want to take a minute to say thanks.

First, I'd like to thank all of the readers. Without you, wouldn't be what it is today. With all of your help this has become a great place to share information, not only from us to you, but with the forums and comments many of you have shared with the community. Thank you for being active participants.

Best of Show at CES 2012

So, CES 2012 came and went this week. For the most part, nothing extraordinary announced at the show, no game changers. In the words of one blogger, this year was "more evolutionary than revolutionary." There were however a few cool gadgets worth mentioning. Read on for videos and write-ups on the three gadgets that stood out most.

ioSafe Rugged Portable Hard Drives

Ok, this is just too awesome not to post about. ioSafe is a company that manufactures and sells rugged computer peripherals that can withstand considerable abuse. To demonstrate their new Thunderbolt portable SSD/RAID disk, they pump a million volts of electricity into one using a Tesla coil. I will never think of Electrostatic Discharge in the same way...

Video below:

CES 2012 is in full swing

The 2012 Consumer Electronic Show officially kicks off today in Las Vegas,
Nevada. Media reporters and bloggers of the world have been busy the last few days with exclusive previews of new products.

The buzz this year seems to be focused on Ultrabooks, or basically ultra-thin laptops that hope to be as thin and cool as the MacBook Air.

This is Microsoft's final year at CES, as heard during their Monday night keynote.

Tablets aren't as big of a buzz as last year since the battle for first place has clearly been secured by Apple's iPad; but keep an eye out for improvements in the competition to battle Amazon for second place.

How to configure DHCP Snooping on a Cisco Catalyst switch

Command Line

A question was asked in the Tekcert forums regarding DHCP snooping configuration. After thinking about writing an in depth response, I decided to just write a full blown blog post.

Everything in this post has been tested in a lab environment with a Cisco 3550, Infoblox DHCP servers, a Netgear router as a "rogue" dhcp server, and a MacBook Pro as a client. The 3550 is configured with ip routing and a layer 3 interface on the subnet where the DHCP servers are located ( VLAN 20 has been created on the 3550 with an interface ip address of All the DHCP server configuration and helper addresses were tested and working prior to implementing DHCP snooping to eliminate any doubt as to whether the DHCP snooping configuration is working or not. So, let's get started.

The Kindle

I've been thinking about picking up a Kindle lately. Everyone I've talked to that has one says they're awesome for reading.

The plane old Kindle seems to be the way to go since all I really want it for is reading, but the gadget geek in me wants to try out the Kindle Fire to play with the extra features. Anyone have one of these that can share there experience in the comments? I'd appreciate it a lot and I'm sure others would too.

GNS3: A Test for Employers

Someone forwarded this post to me...It's a 30 minute test in GNS3 that employers can use to test a potential CCNP-level employee to make sure they know what their doing. What great idea!

Clock rate versus bandwidth

Command Line

If you have ever setup a lab of Cisco routers, you likely have configured a clock rate on one or more serial interfaces. You might have also configured the bandwidth setting on an interface as well. Is one required and not the other? Do they both need to be configured? That's what many people have wondered, including myself when I first started configuring Cisco routers over a decade ago. So I figured I'd create a quick explanation to help people better understand the bandwidth and clock rate commands.


The bandwidth command administratively sets the bandwidth of an interface. When a router boots up, it sets a default bandwidth on an interface which can be seen with the show interface command.

Synology DS411j Network Attached Storage Review

A little over a year ago I was in search of a storage solution for my home network. Several readers provided some great suggestions in the comments area of that first post which helped nudge me toward ultimately purchasing the Synology DS411j DiskStation.

So, here it is nearly a year after picking it up and I must say - this thing rocks! I wish I would have bought one of these sooner. This post provides an overview for some of the best this box has to offer.

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