Category Archives: Networking

Create ACL Rules with Wireshark

Posted on November 26, 2012 by

I stumbled onto this wireshark feature by accident really but thought I would share a little bit about it. Essentially what wireshark does is allows you to review all the captured packets and then a single packet in more detail. Continue reading →

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Cisco Two or More IP Addresses

Posted on November 19, 2012 by

I wanted to take an opportunity to share an experience I had recently and explain how I resolved it.  The situation I walked into was quite ugly.  A small consulting firm had helped install some new switches at a medium sized business.  They basically did a rip and replace.  Before the replacement the network was configured with four VLANs; One VLAN for IP cameras, IP Phones, a few isolated APs, and of course corporate PC data.  The bad news was that the fly-by-night consulting firm had a tech on this job that knew nothing about VLANs.  Can you see the … Continue reading →

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Keeping Time on Cisco IOS

Posted on October 29, 2012 by

When doing any type of troubleshooting I am big on log files. To get the most out of your log files, however, you need the time stamps to be accurate. For time stamps to be accurate you need to ensure your systems are all running with exactly the same time Continue reading →

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Cisco Switch Remote SPAN

Posted on October 18, 2012 by

Capturing network traffic can be a very effective way of solving complicate issues particularly when log files are not yielding useful results. One issue typically is the ability to actually physically perform the capture. To overcome these limitations a Remote SPAN or RSPAN instance can be used. Continue reading →

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