Random knowledge VIII.

You're getting old if you consider sleeping until 0900 'sleeping in'.



When configuring a firewall with IPTables you have to specify the protocol before the port number(s) in each command. Do this:

iptables -A INPUT -s 1.2.3.4 -p tcp --dport 22 -j ACCEPT

and not this

iptables -A INPUT -s 1.2.3.4 --dport 22 -p tcp -j ACCEPT

If you don't, you'll see error messages to the effect of "Unknown arg '--dport'"

When writing Snort rules, there are a few things to keep in mind. First of all, rules come in two parts: the …

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Random knowledge VII.

The /usr/bin/eject utility on a Linux system is a good way of figuring out which machine has what name in the KVM when you're dealing with a rack of machines, many of which are likely to be mislabelled. Use the eject utility to open the CD-ROM drive and see what machine you're really connected to; then update the labels in the KVM's configuration appropriately.



If your fibre-optic network card isn't seeing any traffic at all, try switching the plugs on the card. Some optical network cables don't have colour-coded connectors so it's easy to plug them into the …

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