Currently there are 8 undergraduate PC's and 6 M.Sc. PC's. These computers are running Linux, which is a version of Unix for PC's.
It is important to realize that these PC's are acting as networked workstations, and as such, should not be turned off, or rebooted. There may be remote logins, and rebooting could seriously disrupt the work of others. Furthermore, certain PC's act as NIS and Mail servers, which would mean that any down time would interfer with the normal operation of ALL the PC's. Please think twice before rebooting a PC.
If you would like to use a PC in a true DOS/Win95 environment, please see the system manager first. There is a computer for such purposes in the Library, as well as a laptop for PowerPoint display use.
Password Particulars
The undergraduate Linux PC's have their password files linked
together using NIS. This means that your password on each undergraduate
PC is the same. You only
need to change it on ONE computer, and the rest will know about it.
To change your password on a PC, you should issue the command yppasswd. The old 'passwd' command will merely tell you to use 'yppasswd'!
Ocassionally the NIS server (ungrad1.astro) will not respond. If you suspect there is a password problem, please inform the system manager immediately.
Please note that no other computers in the Astronomy Department use NIS, so if you have other accounts, you will have to change those passwords separately. This now includes the M.Sc. computers.
The Law about Locking Terminals
PC's running X windows can be locked by using the command xlock.
This prevents others from accessing your account if you must leave
the terminal unoccupied for a few moments. Obviously, if a terminal is
locked up for hours on end, other users will be put at a disadvantage, so
the following law stands:
Xlock may only be used if the lab is not full and for a maximum of 15 minutes. This is more than enough time for you to get a caffeine fix. At present we work this law on the honour system, with any abusers being reported to the system manager . If abuse is excessive, 'xlock' will be removed from the system.
Please also remember that you MUST lock the computer, or log out if you must leave the computer unattended. Leaving your account open is a huge security risk.
How to access the Floppy Drive
Normally, under a unix system, any filesystem, including floppies, must
be mounted, but the utility
'mtools' lets you copy files over etc without having to mount the
floppy. You can use the command mcopy:
mcopy a:foo.c ./foo.c
or mcopy foo.c a:
to copy files to and from the floppy drive a:. The manpage on mtools will
give you more information.
The ungrad PC's are also configured to allow users to mount floppies:
mount /mnt/floppy
Thus /mnt/floppy is mounted and the files are in MS-DOS format. Filenames should follow the 8.3 MS-DOS convention, but all of the regular Unix commands can be used (cp, ls, mv ...). When you are done:
umount /mnt/floppy