Info about Linux

[crawford@scruznet.com (Michael D. Crawford)]

Joe Block, jpb@gate.net, sez:

> I want to run linux on this beast and would like some suggestions from the
> list - which of the linux CDs do you recommend?

Hi,

I've got Linux.  Linux comes in different "distributions" - collections of
files that have been integrated into a coherent system.  My distribution is
sold by Yggdrasil, (408) 261-6630, (800) 261-6630, for $39.95.  I like it
because it comes with a single boot floppy, and will run off the CDROM once
it boots, so you can check it out without even having a hard disk
installed.

If you've got time, patience, a good, fast net connection and a whole lotta
floppies, the slackware distribution (and a couple of others) are available
via anonymous FTP from sunsite.unc.edu.  There are also several other
distributions available on CDROM from various vendors.  Check the ads in
the Linux Journal (subs@ssc.com for subscription info, (206) 527-3385, or
at one of the bookstores I mention further down).

If you know about computers, and are willing to put some time into mucking
around fixing little petty problems, you can get a very nice system.  Mine
is a 33 MHz 386 (this is a little too slow for me, but works well), with
8MB of memory (sufficient, should have more), and a nice fast 2.1 GB Fast
SCSI-2 Quantum Empire 2100S hard disk.

I invested in the hard disk as I felt it would be a lasting value in future
computers.  I'm skimping on ISA bus cards for the PC as I want to get a PCI
bus machine, probably a 100MHz 486, in a few months.

You will be able to install Linux, the compiler, basic utilities, and the
kernel sources with the disk space you have.  You'll want to get more hard
disk.  I would recommend installing Linux a couple of times, just to see
how it goes, before committing to a permanent installation.  If you can't
get more disk space, you can leave the Yggdrasil CDROM in your drive all
the time and run the programs off the CDROM.  Slower, but it works OK.

I highly recommend the Linux Bible, from Yggdrasil, whatever distribution
you get.  Read the "How To's" on the various hardware options _before_
purchasing any new hardware.  There are many supported peripherals, but I
understand many of them work only marginally.  For example, the UART chips
generally used in PC serial ports are quite inadequate for driving an
internet connection, as your machine will spend all its time servicing
one-interrupt-per-character interrupts, but a serial card with a 16
character buffer that works just fine is available quite cheaply.

You can FTP the bible from ftp.yggdrasil.com, but you'll want the hardcopy
as it is over 1000 pages.  The cover price is less than the cost of the
toner cartridge you'll burn printing it.  The How To's, the Linux MetaFAQ
and lots of other info are on rtfm.mit.edu and sunsite.unc.edu.

I've used lots of Unix systems, from System V on a 286, to Sun
workstations, Vaxes, and even a Cray running Unicos, and I can say that
Linux is equal to or better than any of them as far as what the OS can do,
in some respects much much better.  (I removed SCO ODT from my hard disk to
install Linux.  I might reinstall it on a second drive just to test my
programs).  There are still lots of glitches, but you have the source code,
and access to comp.os.linux.help, where everyone else has the source code
too - it beats the Hell out of Sun's technical support, IMHO.  With about
two thousand dollars more hardware, I would have a machine I would enjoy as
much as a fifteen thousand dollar Sun, with the source code to boot ;-).

One thing I highly recommend: if you or anyone you know is planning on
setting up a full-time Internet connection, use a Linux box as a router,
running PPP or SLIP out a modem, and ethernet on your LAN.  Even a slow 386
has enough performance to service a SLIP connection at 28 kbaud, and since
you have the source code to the kernel and all the internet server
software, you can implement a firewall any way you like.

I'm contemplating preparing my own distribution, which would be a very
stripped-down Linux kernel and OS utility set, on a small number of
bootable CDROMs, to allow one to install a firewall router on a small hard
disk.  Don't hold your breath waiting for this though.

There is a security enhancement I mean to try once I've set up my own
full-time router (watch for http://crawford.sc.scruznet.com, in about two
weeks, maybe a month).  I want to remove the ability to set the setuid bit
from the kernel.  Trying to set the setuid bit on a file will abort the
process.  Of course you can't install system software if this is done - but
I could boot off a different kernel to do maintenance.  This would prevent
the problem of a hacker breaking in and dropping a program in my path that
the hacker intends me to accidentally execute as root.  There would be ways
to set the bit (writing into the raw disk special file) but it would
require more effort to accomplish.

Crypto enthusiasts in the US and Canada can get Matt Blaze's CFS - I just
got the sources, and haven't tried them out yet, but I understand there is
already a Linux port.

Now here's a puzzler for you.  The People's Republic of China is working
very hard to modernize, but still lacks capital for much hardware
investment, so you see banks using 386 boxes to run an entire bank, if the
bank uses a computer at all.  A couple of years ago I heard that the PRC
signed a deal with some big Unix vendor to supply the nation with computers
and software, for many millions of dollars.  Why don't they use Linux?  The
PRC is certainly not lacking for educated people who could do all the
development they need.

You can get Linux books and CDROM's from the Computer Literacy bookstore on
North First Street in San Jose, and Powell's technical books in Portland
Oregon.  Powell's does mail order, and has a Web page which allows you to
search their inventory for books.  They've got lots of crypto books too,
2600 Magazine and lots of engineering books.  I think the URL is
http:technical.powells.portland.or.us.

Development versions of Linux are available for Macintoshes and MIPS
machines.  If I were to use a Linux Laptop, I would put it on a Macintosh
Powerbook.

Regards,

Michael D. Crawford
crawford@scruznet.com     <- Please note change of address.
crawford@maxwell.ucsc.edu <- Finger me here for PGP Public Key.