I got a call from our Systems and Security guys today to talk about a Wireshark capture they had done from a user VLAN. They had noticed two frames that were destined for some seemingly random host in the same network as they were in, but the source and destination IP addresses reported by Wireshark made no sense. The frames were from a web server to an IP address on our wireless network. The web server is on the other side of the firewall, and the wireless network is on the other side of the controller; there was no reason at all that a packet with that source and destination would show up here.
My prediction about covering network types was wrong. I’m going to puke out some information about neighbor states for now. As is always the case, corrections are welcome.
Yes, it is inevitable that I cover these. I’m sure network types will be next.
I have had my nose deep in several books in preparation for my CCIE R&S written exam, so I haven’t been blogging much at all. Now that I’ve made it to the more familiar topics, I’m hoping to get some notes posted. I’ll start with OSPF message types.
I’m sure you’ve all heard of Cisco IOU by now, and I’m finally catching up with the other bloggers of the world by mentioning it. It’s an executable version of an IOS image that runs on a Unix (or Unix-like) platform and it’s the backend behind Cisco’s Learning Labs.
For the first time ever, I’m headed to Cisco Live – the big Cisco users conference in Las Vegas! I usually don’t go to these things since I wind up just hanging out by myself, but I’m meeting all sorts of people there – from…
If you’ve worked in any particular area for some significant amount of time, you have probably noticed that how much you think you know about a subject has changed over time. This is nothing earth-shattering, and we’ve all had this realization over the course of our lives; it’s come up a lot lately in the course of my career, so I thought I’d share.
This is a surprise, but Cisco has announced the end of life of the 6500 switches that we all know and love.
My ISP is not ready for IPv6. They’ve ignored my emails asking about their deployment strategy, so I gave up and looked at turning up an IPv6 tunnel with a broker.