Cisco Menu for Console Server

By On April 22, 2012 · 3 Comments

Let’s say that you have a Cisco router that you use as console server to connect to your devices in the CCIE testing rack. If you want to allow other people to access your rack for training and don’t want to mess explaining how to connect to different device from the console router, then you [...]

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IP Prefix-List tricky question

By On April 4, 2012 · 5 Comments

A few days ago I did encounter a task in one of these preparation workbooks for CCIE R&S Lab which was very tricky. This task is not a hard one and does not require extensive knowledge (it can be a CCNP level question as well), but the way the question is formulated can create confusion.I [...]

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Packet header graphic representation

By On March 29, 2012 · Leave a Comment

I was surfing the Internet in search of some good drawing representing packet header and I come across five excellent diagrams large enough ( 1050px wide ) to use digital but also for printing. The person behind these excellent drawings is Matt Baxter, but his site (fatpipe.org) is not accessible [...]

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Selective BGP Dampening and parameters tuning

By On March 2, 2012 · Leave a Comment

Some time ago, I wrote about BGP Dampening and how this feature can improve the stability of the network. A lot happened since then and during my experience with different service providers I have seen that BGP dampening can help in the same measure at it can harm [...]

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Fiber Optic basics

By On March 1, 2012 · Leave a Comment

I think all network engineers touched, if not used / patched, as least one time a fiber optic patch cord. As a network engineer you might not necessarily need to understand HOW fiber optic is working. It’s there and it’s working. You just need to plug the patch cord and that that’s it.

Anyway, for [...]

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BGP Conditional Advertisement

By On March 1, 2012 · 2 Comments

BGP Conditional Advertisement – it let the impression of a very complex task. Actually you will find it very easy to implement once you understand it.

In simple words I would say  that BGP conditional advertisement it’s a feature that let you advertise a prefix to one of your neighbors if mandatory condition is satisfied. [...]

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Free Streaming CCNA Voice Bootcamp from INE

By On February 25, 2012 · 1 Comment

I got today a newsletter from INE announcing a freebie. You have it below. Enjoy!

Free Streaming of our NEW
CCNA Voice Bootcamp Course! FOR A LIMITED TIME until March 31st, 2012, get FREE streaming
of the NEW CCNA Voice Bootcamp Course with CCIEx2 #14073
Mark Snow when you [...]

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Cisco NX-OS Malformed IP Packet Denial of Service Vulnerability

By On February 20, 2012 · 2 Comments

Summary

Cisco NX-OS Software is affected by a denial of service (DoS) vulnerability that could cause Cisco Nexus 1000v, 5000, and 7000 Series Switches that are running affected versions of Cisco NX-OS Software to reload when the IP stack processes a malformed IP packet.

Vulnerable Products

Cisco Nexus 1000v, 5000, and 7000 Series Switches that [...]

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Which WAN Optimization vendor will consolidate and expand its market position on 2011

By On January 30, 2012 · Leave a Comment

447 votes  - Thank you all!

I add the results in a blog posts so we can see over years on which optimization technology we were betting in 2011.

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CCIE home rack – Ubuntu persistent net rules

By On November 26, 2011 · Leave a Comment

In one of my last posts, I was writing about my CCIE home rack which has one server that runs Ubuntu + Ethernet Quad cards + Cisco switches. Before connecting the cables between server and Cisco switches, I had one problem that was driving me crazy.

I have [...]

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