As I said already ( here and here ) for gathering Netflow data, especially with security in mind, I deem Nfsen/nfdump to be the best. And with some easy 2-minutes tweaking I can always make it do exactly what I want. By default when you configure Cisco to export both ingress …

Nothing new here , just a round-up of the commands/configs I happen to need from time to time. Google probably has better references for that.I talk about Pf firewall used in FreeBSD, OpenBSD and Solaris systems. Enable and disable firewall: pfctl –e Enable packet filter real time pfctl –ef …

Linux Windows FreeBSD Solaris CISCO routers (IOS) Juniper routers (JunOS) Ping. Many times while debugging network problems of various kinds you need to send some packets of desirable size and don’t fragment bit being set. I list below how to do it for the different equipment/OSes. Let’s …