Author: nick

shape
shape
shape
shape
shape
shape
shape
shape
Standard

Archiving and deleting IOS images

I recently had the need to upgrade the IOS on a Cisco switch (think it was a 3750). As usual, the flash was too small so I needed to remove (and archive/save) the old IOS before putting the new one on. A lot of the images these days include HTML and other things, so are

Standard

Bulk DNS Lookup in Windows Powershell – Better than NSLookup!

In my job I quite often find myself with a whole bunch of host names that I need IP’s for. I found it quite repetitive to keep opening a command prompt and typing “nslookup hostname”, then copying and pasting it somewhere. So I started googling. I have never used Powershell before, so this was a

Standard

Parser Views – Cisco Security

A post on techexams.net recently made me look into parser views in more detail. I read the section in the CCNA: Security Official Certification Guide about them a while back (the entire one page of it), and never really gave it much thought, but I was prompted by the post on the forum to look into them

Standard

MTU / Fragmentation / ACL Tests – Part 2

Now that ICMP traffic is fragmenting across the network, it’s time to change and start using TCP traffic. This is a follow on from MTU / Fragmentation / ACL Tests….Part 1 and I am aiming to find out what happens to fragmented packets when matched to static extended access lists. I’m going to use a program

Standard

MTU / Fragmentation / ACL Tests….Part 1

There was a throwaway line in a book I was reading (the CCNA: Security Official Certification Guide), that said that a disadvantage of ACL’s is: Does not filter fragmented packets with the same accuracy as non fragmented packets. I have no idea why this is true, and after a post on techexams.net, I decided to just set