Have you ever seen the below configuration and wondered what these commands do? And why the MSS value always seems to be 40 bytes lower than the MTU? interface Dialer1 ip mtu 1440 ip tcp adjust-mss 1400 Well, over the course of my next couple of blog entries, I plan to tell you all about them. From my countless number of Google searches, t...
In a previous post I talked about GNS3 memory errors that produced the below log messages when certain IOS images were used and NATing was enabled: R1(config)#int fa0/0 R1(config-if)#ip nat inside % NBAR ERROR: parsing stopped % NBAR Error : Activation failed due to insufficient dynamic memory % NBAR Error: Stile could not add protocol node %NA...
Original (November 2011): 2015 Update: See this page to find out what I’ve been up to over the years since this entry was originally posted. I have received a few e-mails from readers asking me questions about myself and what I do, so I thought I’d write a blog entry about it. I’m a 27 year old Cisco network engineer living in Australia. I wo...
As all Cisco IOS users/Cisco engineers will have seen when booting up a switch or a router, the device will decompress the image file which is represented by a series of # signs that flood across the screen. While it does not take an extremely long time to decompress the image, it can seem like it is taking an eternity if your wanting to get a l...
As most of you know, you can get switch-like capabilities in GNS3 by inserting a NM-16ESW in to a compatible router. This is necessary because at present, dynamips is unable to emulate a real switch. This is because Cisco switches use hardware ASICs to perform their duties and unfortunately it is difficult/impossible for this to be emulated in s...