If you want a full Unix experience with cheaper hardware, I suggest FreeBSD (
FreeBSD tends to behave more like the traditional Unix than most Linux distributions (Slackware Linux is the exception). You will find FreeBSD to require a little more up-front study to understand it, but the benefits are great. I can start with a pair of FreeBSD boot floppies, doing an internet-based install of FreeBSD, and be up and running with a full-featured server within 30 minutes. This includes Apache, PHP, Postgresql, MySQL, etc... Also, the default install is arguably much more secure than a default RedHat or Mandrake Linux install.
I have installed FreeBSD on machines as small as a 486 with 8 MB RAM, and still managed to even
compile Apache/PHP/MySQL from source (although that will take a day or so). For most standard software and utilities, FreeBSD maintains an excellent software repository called the "ports collection", which allows you to install any package quickly and easily, over the net.
But, if you really want to learn Unix, you should learn how to compile software from source, rather than just installing executable binaries. Apache, PHP, etc... these all give you incredible amounts of flexibility when you compile for your own needs, and the performance is usually better, because you can optimize it for your machine.
My recommendation for a good starter machine is something like a Pentium II 350, or thereabouts, with a basic 9GB SCSI hard drive, or a modern ATA-66 or ATA-100 IDE drive, and 256 MB RAM, and a standard 10/100 network card (3Com, Linksys, etc...). You should be able to find something like this almost for free these days. SCSI drives and RAM are more important for Unix than processor speed, because they use processors very efficiently. With this combination, you should have no trouble quickly compiling most of the standard Unix server software out there. -------------------------------------------
Big Brother: "War is Peace" -- Big Business: "Trust is Suspicion"
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