Spam mail bad. Procmail GOOD.

Porkchop <porkchop@example.com> wrote:

>I'm looking to get a procmail thingie setup. I spent a
>few minutes looking at the manpage...seems to be
>written using a non-roman alphabet...!
>Took a quick run on search engines with no luck...so does
>anyone know of a 'procmail for idiots' type webpage?

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Automated SSH login with lussh

If you replace passwords with SSH keys, your scripts can access a remote machine more securely; also, you can set your password to something preposterously long and complex, or disable SSH passwords altogether, thus making it flat-out impossible to break your password by “brute force.” It’s not hard to set up key-based SSH access, but  lussh makes it even more convenient. Read more

A practical iptables firewall in Linux

“We reserve the right to refuse service to anyone,” and iptables is how we do it. Rather than spend a lot of time trying to explain how ipchains begat iptables, let’s jump in. There are enough comments in the code so that everything will make sense, even if we skip much of the theory.
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Introduction to DNS

If you could ask your computer how it feels about domain names, it would say “Looking up domain names is a big pain in my shiny metal tush.” Domain Names were not invented for the benefit of computers. They are purely for people.

Let’s say your name is Bob, and you want to register the domain name “example.com”.
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Unix 101

In the old days, when people walked to school uphill both ways in the snow, the only way into your computer was by using a Command Line Interface, otherwise known as a console. Ah, just you and a blinking cursor. No wallpaper, no stupid, cryptic icons… that’s how computers were meant to be used! Read more

What is SAMBA?

When you connect a Linux machine and a Microsoft Windows machine to the same Local Area Network, they may not automatically see each other. That is, the Linux machine won’t show up in Windows’ Network Neighborhood nor will the Windows disks be available under Linux. Samba changes that — with it, you can quite easily do both.
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jtest - rotate your procmail log

I’m using GNU grep, which allows me to use the -B option to display a few lines of context before the line where it found a match, and -A to display lines after it. mailstat is a helper program which like formail is included in the procmail package. It automatically moves the log file you feed it to a new file with the same name plus the extension “.old”, so in this case, it moves “pm.log” to “pm.log.old”. Read more

LAN101 - The TCP/IP Network

A LAN is a Local Area Network — it’s a fancy way of saying “the two or three computers in this room, give or take the dozen down the hall.” It implies a fast connection — dozens, hundreds, even thousands of times faster than a dial-up modem. It used to be pretty challenging to hook computers together this way, but the parts got cheaper and the software got smarter.
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Hubs, Switches, and Routers

If you want to connect three devices on a 10-Base-T LAN, that crossover cable we talked about in the previous chapter just won’t cut it. It’s time to get a hub, or a switch. To paraphrase the infamous Pitr, “Hub, switch, what is difference?”

They look a lot alike: There is a row of RJ-45 jacks, sometimes called “ports.” (What’s a “jack”? It looks like the hole in the wall where you’d plug in a telephone, only bigger.) There may be some lights to tell you it’s working. There will be some way to provide electric power to it — probably a “wall wart” transformer or a small “brick.” The prices have even started to converge — you can get a modest switch for about the same money as a similar hub.
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What is a ‘Hands-on How-to’?

Any current Linux distribution includes a “doc” directory and under that, a directory full of files whose names all end with “HOWTO”. Each of those files is an exhaustive (and exhausting!) treatment of one subject area — “how to install an IDE disk drive;” “how to install a SCSI CD-ROM;” “how to install… every known form of networking?!”

You might begin to see a problem with this approach; some topics are bigger than others. Adequately covering the entire topic of networking in a single document is just not possible.

Of course, that won’t keep me from trying….
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