/.dtprofile:
Jeremy Sanders
October 2011
The length of the password should be 8 characters. You should not choose dictionary words (in any language) or simple combinations of words and numbers. Ideally your password should be a combination of upper and lower case letters, numbers, and symbols, e.g. eFx!2RxJ. Only the first 8 characters are significant. All passwords are easy to remember when you get used to them! A good way to choose are the initial letters of a phrase, randomly capitalised, and with symbols and numbers randomly added.
You have two standard options to read your email. The first is a graphical email client called thunderbird. The second is the text-based alpine or pine email client.
Some people may be interested in the webmail interface here https://www.ast.cam.ac.uk/webmail/
If you wish to forward your IoA email to another account, you can create a .forward file containing an email address. Your mail will be forwarded to this address. Be careful not to create a mail loop!
ZFS does not use disk quotas. To see how much space you have remaining, use the df command, e.g.
> df -h /home/username/
You are also entitled to additional space (send an email to helpdesk@ast.cam.ac.uk to request it) which is `mirrored': a copy of it is saved to another disk every night. That means if the main disk breaks or you accidentally delete it in a 24-hour period you should be able to recover it.
In addition to this you may request space on one or more `data disks' from helpdesk. Your data will not be backed up automatically--you must do this yourself.
You need to use the df command if your disk uses ZFS, otherwise use the command quota -v. You have a current usage, a quota (where you will receive warnings) and a limit (where you cannot create new files). Going over your quota leads to strange errors which are hard to diagnose, so keep an eye on it.
Note that firefox stores its cache in your homespace. You can try to clear its cache to free up some space. You can set the cache size to a small value to stop it getting too large. A further trick is to move it to a data disk and use a symbolic link to map the data disk directory to where the cache usually resides.
Realise that RAID protected directories don't protect you from stupid mistakes. You can accidently delete files very easily and you can never get them back.
Alternative ways of backing up data are to copy data to different disks on different computers in other locations. The rsync command is a very useful tool to only copy the files that have changed on the source system.
rsync -av /home/foo/indir/ /data/foo/outdir/This will replicate any files in indir to outdir. It will not delete any files in outdir that no longer appear in indir. You need to add the -delete option in order to get this.
If you want to copy files to another computer over ssh, you can do this:
rsync -av /home/foo/indir/ username@somecomputer.cam.ac.uk:/data/foo/outdir/The username@ part is optional if you have the same username on the destination computer.
The tape is accessed using tar and the tape device, which tells tar what tape drive to use and what level of compression to use on the tape. The command used to backup the current directory is:
tar cvf tapedevice ./
where tapedevice specifies the device. tapedevice takes the form /dev/rmt/[0-127] [l,m,h,u,c][b][n] (no spaces) (see the users' guide for details on what the letters do), e.g. /dev/rmt/0. This command will overwrite what is on the tape and rewind the tape afterwards (add n to 0 to stop the rewind). This command backs up the current directory and its contents (and subdirectories inside it, but not symlinks). Do not use an absolute directory instead of ./ to back up - there is a bug on Sun tar.
Use tar tvf tapedevice to list the contents of a tape. Use tar xvf tapedevice to extract its contents into the current directory. Other tape commands are (see man mt):
mt -f /dev/rmt/0 offline <-- rewind and eject tape mt -f /dev/rmt/0 rewind <-- rewind tape mt -f /dev/rmt/0 status <-- what is the drive doing? mt -f /dev/rmt/0 eom <-- go to end of tape contents
If your work is data intensive you should run your programs on the machine hosting the data if possible, otherwise it will be slow as the data will have to be transferred over the network.
The command to log into another machine is ssh (secure-shell). It is even possible to run graphical programs over ssh from a remote computer (thanks to the wonders of the X Windows System). See the Users' Guide and man ssh for much more information. Note that the computers you can log into remotely are restricted.
ssh cass80 [or ssh cass80.ast.cam.ac.uk] [type your commands here in this new shell] [type exit to return to your computer]
If you are planning to run a long job (longer than a few minutes), you should nice your job. Niced jobs run at a lower priority level than interactive jobs (such as the session of the person sitting in front of the computer). Nice levels run between -19 (high priority) and 19 (low priority). Standard programs run at level 0. Normally you would you a command like
nice +19 myjobto run the job at level 19.
The easiest way to see how loaded a computer (how many things are running on it) is to use the top command which interactively shows the `topmost', or most CPU intensive, jobs. Press q to exit it (press ? to get other possible commands).
It is hard to find a computer free on which to run a job (or several), but there is another, easier, way to do this called the Sun Grid Engine. It allows you to send a job, setting the requirements for the computer you need, adding it to a queue to be run. Jobs are run fairly (nobody can hog the queue) from the queue among the free computers. The best documentation is in the Users' Guide.
You can make terminal sessions that you can disconnect from and reconnect to later using the GNU screen command, which also allows multiple terminals in the same connection. Type screen to start, and run your programs. If you want to disconnect, type ctrl+a followed by d (most screen commands use ctrl+a followed by something - try using ctrl+a then ?). You can then reconnect later by logging into the computer and typing screen -r.
The lp-style printing commands are rather random. I apologise for them (even though they are not my fault). The lpr-style commands are more coherent, but don't allow you to set printer options.
To determine which printer you want to print on, ask someone which is nearest, or note down the name which is stuck on each one. The command to view what is on the queue - list of jobs to be printed - is:
lpstat -o printer_namewhere printer_name is the name you should remember. To print a file on the printer:
lp -d printer_name filename(I told you they were random!). If you realise you didn't want to print that file, find the number of the job you printed (see the output of the lp command or repeat the lpstat command), and do
cancel job_name(who knows why they called it cancel and not lpcancel!!).
You can alternatively print text with the following commands (which are more coherent), but they are not standard in Solaris, so don't blame me if they break! Subtly the lpr command is different to lp in that it is safe to delete the file it is printing before it prints.
To view a printer queue:
lpq -Pprinter_nameTo send a job:
lpr -Pprinter_name filenameTo cancel a print job:
lprm -Pprinter_name job_id
setenv PRINTER printer_nameto make printer_name your default printer. You won't need to use -d on the lp command for that printer after logging in again. Note that any programs started from firefox will not see this change unless you log out and log in again.
# print one side of paper only # (normally prints on both for black and white) lp -d printer_name -o simplex filename # print on both sides of paper # (normally single for colour printers) lp -d printer_name -o duplex filename # print on transparancies for colour4 and colour5 lp -d printer_name -o trans filename # print on transparancies for colour3 lp -d colour3 -o mtypeTransparency filename # use manual feed tray (stick your own paper in) lp -d printer_name -o mpt filename
Also if you use StarOffice/OpenOffice for presentations, don't use a dark background as that will waste lots of the same colour for each page. Leave backgrounds blank if possible.
#!/bin/tcsh xrdb -load $HOME/.Xdefaults xmotd & gnome-session
The xmotd line is optional and shows the message of the day.
Alternatively you can use the faster fvwm window manager. You need to
have the following line in /.dtprofile:
SESSIONTYPE=xdm
You will need to put your X startup script in
/.xsession rather than /.xinitrc
See below for details on logging in using other methods (ssh and X over ssh).
You can only log in directly to the muon1.ast.cam.ac.uk, muon2 and muon3 gateway machines under the current security arrangements.
If you want to run graphical programs remotely to a Windows computer, you either have to use commercial software (which costs money), or use a free program like Xming. A commercial possibility is WinaXe at http://xwinpro.com/xwinpro.html which is available in a 30 minute demo mode.
Xming is free software and is available from http://www.straightrunning.com/XmingNotes/ Here are some instructions to get going. It's not too bad when installed.
If something goes wrong, close the X server by right clicking on the X in the bottom right if it is there, then choose exit. Start again by running Xlauncher.
You can start a complete desktop environment by choosing `Single window' in the first dialog box, and `gnome-session' as the program to start running.
You can simply type
ssh -Y -C username@muonX.ast.cam.ac.ukwhere username is your username and muonX is the gateway system to log into (muon1 or muon2). -Y means forward the X connection (so you can start graphical applications), and -C means compress the data sent over the network (which speads things up over a slow network). You can start further applications (including gnome-terminal) from this logged-in window.
If you want to run an entire desktop from the remote system, there is a slightly more complex way of doing this. Firstly start a second X session by typing in a terminal window (make sure you have the spaces correct):
xinit -- :1When the second session has started, you should get a single terminal window on a grey background. Move the mouse over that terminal, and run the ssh command above. After logging in type gnome-session. This should start up the remote session.
ctrl+alt+backspace should kill off this second session should you need to.
To run it, go to `Applications', then `Utilities' and start `X11'. A terminal window should then pop up. From that terminal window you can type the ssh command to log in remotely and forward connections:
ssh -Y -C username@muon1.ast.cam.ac.ukmuon1 could be muon2 here.
StarOffice includes some elements not present in OpenOffice, but OpenOffice is available to download for free on your home system. You can open Microsoft Office documents with either. OpenOffice is very handy for making presentations (like Powerpoint). See the Users' Guide for help in setting up both.
If you are using the tcsh shell (the default), you need to run the command
source /opt/ioa/Modules/default/init/tcshSee the users' manual for other shells. This command needs to be run in each shell, so add it to your .mytcshrc file to get it run by default.
After you have done this, you can use the module commmand to see what is available (at the time of writing):
> module avail ... ---------------- /opt/ioa/Modules/modulefiles -------------------------- fftw/2.1.5_double gsl/1.14 openmpi/gcc/4.5.0/1.4.2 fftw/2.1.5_float hdf5/1.6.10_parallel openmpi/intel/11.1/1.4.2 fftw/3.2.2_double hdf5/1.6.10_serial openmpi/sunstudio/ss12u1/1.4.2 fftw/3.2.2_float intel/11.0 python/2.7 gcc/4.5.0 intel/11.1 pythonmod/pyfits_2.3.1 gsl/1.13 intel-mkl/10.2.4 sunstudio/ss12u1If you want to know what one of these module files does, use the module help command. To load a module you can use module load, e.g.
> module load gcc # load latest gcc moduleYou can add a version if you want a specfic version of the software.
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The translation was initiated by Jeremy Sanders on 2011-10-02