Monthly Archives: July 2011

Possible Reasons for LAN Traffic Congestion

If you are experiencing slowness on your LAN here are some possible reasons that you can investigate:

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Useful FTOS “show” commands

There are several FTOS “show” commands that can provide very useful information regarding Force10 Networks switches/routers. I have outlined a number of these very useful commands with a short description of each below. However, keep in mind that although most … Continue reading

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Use Perl’s regex to count the # of words in a file

In the below code I use Perl’s regex capabilites to count the # of words in a file. Notice I used “\s” in the regex expression to account for not only spaces but also tab and new line characters. In … Continue reading

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Port Monitoring on Force10 Switches

In this lab I will demonstrate how to do port monitoring on Force10 switches and capture the packets using a network protocol analyzer (Wireshark in this case). Port monitoring allows the copying of all incoming/outgoing packets on a specific port … Continue reading

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Scalar and List Contexts in Perl

One of the most important concepts to understand in Perl programming is that of evaluation based on context. In Perl, an operation such as an assignment or function call can give two different results based on the context of the … Continue reading

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Setup VRRP with Force10 Switches

In this lab I setup Force10 switches with Virtual Router Redundancy Protocol (VRRP). VRRP is a redundancy protocol used to eliminate a single point of failure between a gateway and its respective hosts within the same subnet. I use three … Continue reading

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Unix shell script – convert Mac ASCII file to Unix ASCII file

With some applications like Microsoft Word you can save a file in ASCII format. However, for new lines Macs use a carriage return (ASCII character 015) while Unix uses a linefeed (ASCII character 012). If you save the file as … Continue reading

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