jtest - rotate your procmail log
Posted on October 29, 2007
Filed Under Mail, Unix | Leave a Comment
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
Posted on October 29, 2007
Filed Under Networking, Unix, Windows | 1 Comment
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
Posted on October 29, 2007
Filed Under Networking | Leave a Comment
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’?
Posted on October 29, 2007
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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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