This penguin walks on a bed of blue screens of death!

[Lincoln Peters]

>From: ME <dugan at passwall.com>
>Reply-To: <talk at nblug.org>
>To: talk at nblug.org
>Subject: Re: This penguin walks on a bed of blue screens of death!
>Date: Thu, 4 Oct 2001 17:44:24 -0700 (PDT)
>
>On Thu, 4 Oct 2001, Lincoln Peters wrote:
> > That is, it works pretty well for me, because I know what I'm doing.  I
> > couldn't run GNOME or KDE on any of the workstations because they only 
>have
> > 64MB of memory (aack!) and it is impossible to set up any sort of swap
> > device when netbooting.
>
>This is not entirely true, but the alternatives are scary depending upon
>your resources:
>
>If you have a netboot system that has a local physicaly HD that is
>recognized by the OS, then you can use that.
>
>If there is a disk, but they dont want you to format it or partition a
>swap, *and* it is a filesystem that linux recognizes and can do write
>access without serious risk (FAT32 not NTFS for example), then you can
>mount the local disk on a separate tree, then verify it has at least the
>amount of space you want to use as swap, and then use dd to write out that
>size from /ev/zero, then losetup it to a loopback device, and then swapon
>the loopback device. Blammo! Swap!  (scary, no?)

Can't do it.  The hardrive uses NTFS.  I might try it if the harddrive used 
a filesystem that could be safely written to (e.g. FAT32), but the closest I 
can come to that would be to use a ZIP disk for swap (now THAT's scary!)

>
>You want even more scary? Ok then! You asked for it!
>
>Set up the server to offer one quota (user) controlled NFS export by
>username (host) which maps to an /etc/hosts name for each IP based host
>and also is listed in the nebooted /etc/hosts file, and then have each
>client locally mount from the server their own special rw NFS mount (quota
>limited) with IP restrictions for only their IP address to rw, and then
>when it is mounted somewhere, do the same as above with dd, and losetup
>the file with the loopback interface to a /dev/loopX device, and then
>swapon that /dev and do swap space over NFS over the net with a loopback
>file. (Ewwwwwww!) I told you it was scary. heh heh ]:>

Might work, but the server only has a total capacity of about 5.25GB in its 
three harddrives, and the NIC card only does 10Mbps.  I don't have space for 
that many swapfiles, and the NIC is under high pressure as it stands 
already.  Sorry, I can't afford better equipment.

>
>Want yet another one that is almost stupid (an appears to be stupid at
>first glance): enable a ramdisk of set size, mount it, dd a file in that
>ram disk, losetup to dev, swapon the dev (ick!) At first it looks like you
>are robbing peter to pay Paul, and this is true. It also seems like a bad
>idea, and is mostly a bad idea, but even having a swap of 1-4Mb helps
>quite a bit as the kernel does some things with unused libs in memory as
>it starts to use swap. No swap would mean you run out of memory for these,
>and bad things happen when you run out of memory. (Did I scare you yet?)
>There may also be faster ways of doing this than using a ramdisk as a
>mounted filesystem as /dev/ramX may be mountable as a swap directly. (not
>sure, but would rmeove some layers of abstraction.)

You're right.  It is rather scary.  That ZIP disk is looking better all the 
time.

>
>OK, I am done being scary. No, this is how I normally look. OK, I have not
>got much slee lately. Lets move on.

I know the feeling well.

>
> > Even worse, the "Programs" section of the menu is empty!  I can't see 
>any
> > way that anyone besides myself would feel comfortable starting programs
> > using an XTerm!  I guess I'm somewhat spoiled because Ximian GNOME runs 
>on
> > my home computer (it has 256MB of memory), so I have no experience with
> > setting up FVWM2 or any other session manager besides KDE.  Can anyone 
>clue
> > me in on how configure it?
>
>"There is a file..." that contains all of the config stuff for the window
>manager. Locations vary from distro to distro. When you figure out the
>format of the file, you can add your own stuff to the window manager and
>the desktop, program listings etc.

That makes sense.  It would be nice if it had a Control Panel, but I can 
probably figure it out.

>
>For my debian system /etc/X11/fvwm* each have their own config files that
>do their own thing. I used fvwm(1) a long time ago, and it was fun to
>customize. fvwm2 and fvwm95 are a little more complex, but they can be
>configured much the same way with newer and extra features in their
>respective config files. Also, users may have their own extensions to the
>window manager display in their own directory with fvwm2/fvwm95, but I
>dont think that was a part of fvwm(1).

I guess I'll have to plow through the documentation and figure out what I 
need to do.

>
> > A few other minor issues exist, but I want to have _something_ that is
> > actually usable for ordinary people before I tackle them.  If this seems
> > daunting right now, I can't imagine what it'll be like when I try to 
>port
> > this to the iMacs!
>
>Tricky as you will need a whole new binary package/suite to send to them
>compiled for the 680x0 or PPC (probably PPC). Netboot imacs with MacOS is
>an alternative, but it is heavily server biased and should really have
>high speed drives on the server + high speed netwrks for anythign over 10
>stations.

I know.  Hopefully I can get another harddrive, cross-compile the RedHat 
source RPMS, and install the cross-compiled system there, but at the moment, 
it still gags because there are two kinds of Dell OptiPlexes that are ALMOST 
the same (I wonder who had the bright idea of putting two video cards in one 
computer while only providing one monitor?).

Until then, I'll probably need to get a contraband Norton Utilities rescue 
CD for Macintosh and use it to disable the security software.

>
> > (Some of you may remember that I was originally trying to use the 
>server's
> > root filesystem as the workstations' root filesystem.  When I tried 
>that, I
> > found that the necessary changes in the initscripts were so extensive 
>and so
> > weird that I finally said to myself, "Ah, ***** it," and got the third
> > harddrive for the workstations' root filesystem.)
>
>Yes, but if this is IDE and is not on its own IDE/ATA interface, you may
>notice some client based performance issues with speed. Even ATA100 is no
>match for good SCSI-3 style 160MB/s LVD controllers with matching
>drives. RAID can help (depending).

The third harddrive is an older SCSI, but do you really think that a SCSI-3 
would work on a 486?  This server is essentially built from spare parts that 
were lying around in my garage and in some of my friend's garages (you 
wouldn't believe the tobacco smell when I connected it to my brother's old 
monitor!).  It doesn't even have a PCI bus (or a VESA bus, for that matter)!

In case it helps, though, here's how the harddrives are set up:

One IDE controller, don't know what kind (but it's not built into the 
motherboard):
hda: 250MB total capacity, one 32MB swap partition, the other 218MB are used 
by the root filesystem (ext2 filesystem).
No hdb.

Two SCSI harddrives on an Adaptec AHA-something ISA controller:
sda: 2GB total capacity, 1GB for /usr (reiserfs filesystem), 1GB for /home 
(reiserfs filesystem).
sdb: 3GB total capacity, all used by /netboot (ext2 filesystem).  /netboot 
is the filesystem used by the netbooting workstations.

BTW, the workstations use tmpfs for /var/cache, /var/lock, /var/log, 
/var/run, /var/spool, /var/state, and /tmp.  They are prepared at boot-time 
using a few tarballs in a hidden directory.


If this project turns out well, I might be able to convince the school to 
buy a better server.  Of course, what I REALLY want are a few of those 
server racks that Dreamworks was showing pictures of at LinuxWorld!

>
> > Get your FREE download of MSN Explorer at 
>http://explorer.msn.com/intl.asp
>
>And what if I dont want to get my own copy of MS INternet
>explorer. Huh? May as well say, "Come get your free nuclear waste! Free
>biohazard baggie with random hospital trash included for free!

The Hotmail server tagged that onto the end of the message; I can't stop it. 
  If I thought that any Microsoft products and/or services worked (except 
Hotmail, which I hear runs on BSD and Qmail), I wouldn't be trying to 
introduce Linux into our schools.  It will probably tag that same MSN 
Explorer message onto the end of this message, too.


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