by Jon Drane
It is a distribution of the Linux kernel and some utilities which comprise a usable operating system suitable for processing SETI@home work units. It unpacks its file system into memory so it will run on systems without a hard disk. It is a way to use those old PCs that we all have lying around as dedicated work unit crunchers.Audience:
Anyone interested in running seti@home client software on a PC which is unsuitable for one of the conventional seti@home client platforms (i.e. Windows 98, Windows NT, big Linux, etc.) due to lack of memory, little hard disk space (or no hard disk at all!).Minimum hardware requirements:
No great level of technical expertise is required, but confidence with a command line interface the like MS-DOS prompt in Windows NT or Windows 98 would help, as would familiarity with the commandline SETI@home client. If you know what 'boot from a floppy' means, this is for you. If you want to learn more about Unix or Linx, check any of the many available books or look for resources on the web.
A PC with 386 or better CPU, VGA video adapter, monitor , keyboard, 3.5" floppy disk drive and 8 Mb RAM.Hardware requirements to crunch a Seti@home WU before it's timed out and sent to someone else:
A separate PC running the SETI@home client with connectivity to the SETI@home servers is needed to send and receive data files.
As above with approx. 486DX/33Mhz CPU. The DX designation says that the processor contains a math coprocessor. Without a coprocessor, the math required would occupy an unusable time frame. SX class processors are not useful with the SETI@home client.Software requirements:
A mini linux - tomsrtbt V1.7.185 is discussed here.Other requirements:
A suitable SETI@home client [i386-pc-linux-gnu-gnulibc1-static] from the SETI@home website.
3.5" floppy disks to transfer files to another system with SETI@home client software to fetch the units and send the results back. tomsrtbt contains some IP and IP/serial networking functionality - but I can't get it working. Any feedback on successful connections to the Berkeley servers will be appreciated.Installation:
Read the tomsrtbt FAQ for instructions on making the bootable floppy. Pay particular attention to the warning about the remote (but real) danger that creating the bootable floppy could damage your floppy drive.Getting started with tomsrtbt:
Boot the PC off the floppy, several prompts will appear but you not need to enter anything. The system will boot to a default setup (US kbd).
At the login prompt, typeA basic introduction to some commands in tomsrtbt:root[enter]At the password prompt, type the default password (it is helpfully displayed).xxxx[enter]You should now be logged in and see a hash (#) prompt
You may remove the boot floppy. Linux is entirely memory resident.
There are 4 virtual terminals available in tomsrtbt, to switch between them hold down [alt] and press [f1]..[f4]. the default terminal is f1.. Linux multitasking multi-user system.
Command history and editing is available with the up, down, left and right arrow keys.
To read the manual for a command (e.g. ls) typeman ls
ls list files and directories, cf DIR in DOS]Run the SETI@home client:
cd change directory - directories are delimited by '/index.html' characters - cd with no directory specified cd's to your 'home' directory
pwd print working directory]
mv move a file (or directory), a bit like DOS command REN but you can also move a file or directory into a different directory]
mkdir make a directory]
df disk free - show mounted filesystem, space used and space free for each]
mount mount (make available) a file system]
umount unmount a file system, you must ALWAYS umount a mounted floppy drive before changing the disk]
man manual - show helpful information about a command, e.g.. man ls]
tar create or unpack files from a un*x standard archive file - called a tar file - the unix clients come in tar format
You will need two DOS format floppies.
Copy the Linux SETI@home tar file downloaded from SETI@home website onto the first DOS format floppy.
Download a work unit from SETI@home using the same version of client as the one you intend to use on
linux. (eg 2.4 text client for WinNT)
Use the -stop_after_xfer option and copy ALL the *.sah files to the second DOS format floppy.
Boot the tomsrtbt floppy.
Login to tomsrtbt as root.
Insert a DOS format floppy.
Type the following commands
Backing up the progress made by SETI@home:mount -t vfat /dev/fd0 /mnt(This copies the client and *.sah files to the memory resident /tmp filesystem)
cp /mnt/* /tmp/seticd /tmp/setiThe ./ characters specify the current directory - required in linux and un*x, (unlike DOS).
To monitor the client progress, login to another virtual terminal (Alt+f2).cd /tmp/setiThe number after 'prog=' goes from 0.00 to about 0.97 as the work unit is processed.
It is recommended that you start a task in another virtual terminal (alt+f3) to write the *.sah files back to floppy periodically - to reduce the amount of work lost if the system goes down.To restart the current workunit :while trueThis gives a backup period period of 900 seconds (15 mins) between backups of the data files.
cp /tmp/seti/*.sah /mnt
reboot tomsrtbt and login as root. Insert the work floppy (containing setiathome executable and *.sah files)To return the completed result and fetch another work unit :mount -t vfat /dev/fd0 /mntand proceed as in the section Run the SETI@home client above, remembering also to start the backup process in another virtual terminal.
When the setiathome process is finished it will return to the hash (#) prompt, stop the backup process running in the atl+f3 terminal with Ctrl+C.
Copy the seti@home work files to the floppy before unmounting itcp /tmp/seti/*.sah /mnt/After umount returns to the hash prompt - it is safe to remove the floppy.
NB if umount returns a 'device busy' message - the cause is probably one of the terminals being cd'd to /mnt, find which one with the pwd command and cd / before trying the umount command again.
Copy the *.sah files from the work floppy to a seti directory on your machine with internet connectivity
Start seti@home with the -stop_after_xfer option to return the result and fetch a new work unit.
Copy all the *.sah files from the seti directory of the connected machine to the work floppy
Continue from the instructions for Run the Seti@home client above - there is no need to reboot tomsrtbt if it is still 'up'
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