Transient "Beowulf" cluster of Erlang nodes.

[Miguel Barreiro Paz]

> Now I need to get Knoppix to work, modify it, and launch Erlang on
> bootup as a service, perhaps. Unless there's a way of running a "pure"
> Erlang node on a PC?

#message{offtopic=almost, size=toolong, contents="

Modifying Knoppix is easy:
- install the cloop module (compressed loop filesystem) and utilities
(apt-get install cloop-src cloop-utils)
- compile the cloop.o module ('make' in /usr/src/modules/cloop)
- copy the whole CD to your disk (say, /home/pmander/knoppix/cdroot)
- mount the large compressed filesystem image and copy it:
 # insmod cloop.o file=/home/pmander/knoppix/cdroot/KNOPPIX/KNOPPIX
 # mount -o ro /dev/cloop /mnt/knoppix

- copy (keeping owners and permissions) the whole compressed image to your
disk, say to ~pmander/knoppix/cloop. chroot to that directory.
- configure your network by hand, add debian mirrors to
/etc/apt/sources.list and install or remove packages at will (apt-get
update ; apt-get install erlang ; dpkg --purge gnome-base ). Edit and
configure everything at will (respecting the autoconfig scripts).
- exit the chroot, and create a new KNOPPIX compressed image.

#!/bin/sh
# make-compressed-image - Makes a compressed KNOPPIX image
mkisofs -R -l -V "KNOPPIX" -hide-rr-moved -v \
 ../cloop | create_compressed_fs - 65536 > /home/pmander/knoppix/KNOPPIX/KNOPPIX

- Create an ISO CD-ROM image:
#!/bin/sh
# make-bootable-cd - Makes a bootable KNOPPIX ISO image
mkisofs -l -r -J -V "KNOPPIX" -hide-rr-moved -v \
 -b KNOPPIX/boot.img -c KNOPPIX/boot.cat -o \
/home/pmander/knoppix/knoppix.iso /home/pmander/knoppix/cdroot

(untested scripts but should work - similar enough to my setup)

-Burn your knoppix.iso image into a CD (...preferably a rewritable ;-))
and enjoy ("cdrecord -pad speed=24 dev=0,0,0 blank=fast" or something like
this adapted to your system will blank the rewritable quickly).

Disclaimer: been a few months since I did it, so things may have changed a
bit. You will have to rebuild the compressed image and then the ISO every
time you change a single file, and it hurts, so make few mistakes. You
will need 512-1024MB RAM for this procedure to take a reasonable time if
the compressed image is large. I'm not responsible when/if your computer
catches fire. It will.


A more interesting setup would be a PXE boot environment that boots
directly into an erlang system, with remote I/O.

Regards,

Miguel

"}.