There’s a lot of noise on the Internet. I’m not talking about certain news sites, either; I’m talking about stuff like port scans or attempts on weak services from all sorts of bad people on the Internet. A large chunk of that noise can be filtered by the edge routers, taking some of the load […]
Happy new year, all. I’m finally over my hangover from the party and ready to blog. Everywhere I go, I always wind up in a debate about how to alert on log messages as they come in. I was at the grocery store yesterday, and the cashier told me that she had a list of […]
Here’s a short but nifty video I found on the history of the Internet. We all say “DARPA” or “ARPANET”, but I had no idea that the French developed the router first. History of the Internet from PICOL on Vimeo.
Did anyone notice (or care about) the leap second? I did neither. Here’s some cool output from Kevin Oberman on the NANOG list, though. bash-2.05b# date Thu Jan 1 00:59:58 CET 2009 bash-2.05b# date Thu Jan 1 00:59:59 CET 2009 bash-2.05b# date Thu Jan 1 00:59:60 CET 2009 bash-2.05b# date Thu Jan 1 01:00:00 CET […]
Stretch at Packetlife has a lively little write-up on the Australian government’s attempt to implement a nation-wide web filtering service. From Packetlife.net: Setting aside the myriad of technical barriers to implementing such a system, the most obvious question is, “who decides what gets blocked?” When a corporation implements a web filter, it does so in […]
I thought I’d throw an easy one out before taking off for the holiday. Merry Christmas, Hannukah, Kwanzaa, Saturnia, etc., to all. A few years ago, I was looking through some Cacti graphs of gigabit trunks between 6500s and noticed an abrupt change in traffic. The graphs were nice and smooth at around 135Mpbs until, […]
I don’t know if I’m mad or honored, but I received about 400 forged email bounces last night (isn’t SMTP wonderful?). I realize that some people have gotten spam from my domain, but I had nothing to do with it. I’m going to check out the bounces when I get a chance and see what […]
Did you catch the article on setting up fault tolerance on the CSM? In that article, I mentioned that Cisco recommends a dedicated trunk for the FT VLAN if you have two HA CSMs in two chassis. Discuss amongst yourselves while I drone on. Why should you set up a dedicated trunk for this stuff? […]
There are three different ways that a CSM checks for the health of the servers — active probes, inband health checking, and inband HTTP monitoring. Let’s talk about active probes. Active probes (or just probes) typically send traffic to one of the RIPs of a serverfarm, do some stuff, and give a pass or fail […]
We have a location that’s a few blocks down from the main office here, and we were reviewing the circuit size to make sure it was sized properly. Since not one person knows what’s going on and the trending graphs gave us conflicting details, one of our network dudes took me down to the site […]