Here are some common questions and answers about the use of the
maths computer system. If you can't find an answer here or if
you find something is broken of if you have any suggestions
please send e-mail to ops@maths.tcd.ie.
Disclaimer: Apologies for old information in this page. We hope to update it soon. (14/11/2011).
You can change your password only when you are logged on to
salmon. Then you can give the command passwd
which will ask for your old password, and then the new one.
If the new password is too easy to guess then the password program will complain and make you choose a different password.
When you have finished your password will be changed on salmon. The rest of the machines will use your old password until midnight, when they will be updated.
If you have forgotten your password, please
email ops@maths.tcd.ie (from another email address!) to
make an appointment
or ask in the School office (room 0.6).
We don'yt send passwords by email.
Please bring your ID card so we can check
who you are!
tcsh, which is fine for most people. We do not
allow people to change their shells themselves, but if you
mail ops@maths.tcd.ie we will be happy to change it for
you. (We also have sh, csh, bash, zsh, though the
dot files for these are not as well tested).
newaddress@work.com)
you should make a file called .maildelivery, which
contains the line:
* * | A "/usr/local/bin/resend -r$(sender) newaddress@work.com"
Note - on many systems you can make a file called .forward,
containing the e-mail address you would like mail forwarded to. Unfortunately
this does not work on the maths system (as we use MMDF, not sendmail).
More info about your maildelivery file can be found in manual pages:
man maildelivery
.maildelivery, which
contains the line:
* * | ? /local/mmdf/bin/rcvtrip $(sender)
tripnote with a message explaining
why you are away:
Hi, I'm at a conference until Monday 9 August. I will read
your email when I return. If you need to contact me
urgently call my mobile phone. - John Smith
More info about your maildelivery file and rcvtrip can be found in manual pages:
man maildelivery and man rcvtrip
.maildelivery file with the following lines
at the top:
* - | A "/usr/local/bin/spamassassin-true-if-spam"
* - > +11! junkmail
This will put all the mail which Spamassassin thinks is junk into
a file called junkmail.
Occasionally, Spamassassin may mistake real e-mail for junk e-mail.
You may want to check the contents of the junk mail folder from
time to time. This can be done with the command
mutt -f ~/junkmail or
pine -f ~/junkmail,
depending on which mail program you like to use.
If you trust Spamassassin not to make any mistakes, then could reject or destroy mail instead of putting it in a junk-mail folder.
.spamassassin/user_prefs and adding addresses to the
whitelist_from list.
Unfortunately clamav has not been working on our system for a while, but with luck it will be enabled again soon (11/2011).
Viruses via e-mail will most often only affect people who use Microsoft Windows, and so users of Unix systems tend to be able to ignore them. However, you may want to filter out viruses in your e-mail, either because you read your maths mail on a Windows PC or because you find receiving this sort of junk mail annoying.
If you want to filter virus mail, Clam AnitVirus is available.
To get Clamav to filter your mail, you need
to make a .maildelivery file with the following lines
at the top:
* - | A "/usr/local/bin/clamscan-true-if-virus"
* - > +11! virusmail
This will put all the mail which Clamav thinks is a virus into
a file called virusmail.
You can use Spamassassin and Clamav at the same time by putting
both the Clamav lines and the Spamassassin lines in your
.maildelivery. You could even file the rejected mail
from both into the same mailbox, by changing virusmail
into junkmail in the lines above, for example.
If you would prefer to discard viruses, rather than
filing them in a separate folder, you could replace the Clamav
lines in your .maildelivery with:
* - | A "/usr/local/bin/clamscan-true-if-virus"
* - destroy +11!
.maildelivery
file. Say you want to delete all mail from junk@mail.net
then make a .maildelivery file containing the line:
From junk@mail.net destroy A -
not-junk@mail.net!
You can replace the destroy with reject
in which case the person will receive a piece of mail saying that
their mail was rejected. For examples see
/local/mmdf/premaildelivery
or look at the man page for maildelivery.
ssh, an encrypted
communications protocol.
A number of programs are available for this... firstly,
the Java applet we have set up at
http://www.maths.tcd.ie/ssh/
(convenient if you're traveling too!).
There are also a number of programs you can download to your own
computer... for Windows, the best one we have come across is
PuTTY.
Also available, but a larger download, is
TTSSH.
For UNIX, you can install OpenSSH,
which will require OpenSSL to
be installed also.
To use this program say fix-my-account (or if things are
really messed up /usr/local/bin/fix-my-account). Now answer
the questions it asks you - it will not change anything without asking
you.
There are two reasons for this. If the problem is intermittent or short-term (less that a day) then it is probably a network problem and you will have to wait for it to go away.
If you never seem to be able to get at the outside world your browser (firefox, iceweasel, opera, konqueror -- there are lots installed) preferences are probably wrong. You need to find the proxy settings (either in your browser or in your desktop settings). For instance in firefox/iceweasel that is under Edit -> Preferences. Select Advanced tab, then Network, then Connection settings.
The simplest is to set it to "Auto detect proxy settings" and that should work now (in most browsers).
If that fails, the next best is to set "Automatic proxy configuration
url" to http://wpad.maths.tcd.ie.
In the worst case (say with browsers in a phone, maybe, or skype perhaps)
you may need to manually set proxies to proxy.maths.tcd.ie
port 80.
(This section updated 11/2011.)
rm ~/.netscape/lock
If the person has a maths account you could try
finger -l name, where name is the first name or surname
of the person you are looking for. This may produce a lot of output,
but will probably list the person you want.
If you are looking for a college e-mail address or phone numbers you can say consult the people finder page on the College local web page http://peoplefinder.tcd.ie/pls/peoplefinder
Staff in the School are listed on our web page http://www.maths.tcd.ie/people/ and there is always your favourite search engine.
The basic thing is that the files that constitute your personal
web site must be in a directory ~/www (that is a
subdirectory www of your hime directory, and there are issues
with read and execute permissions.
So you must create the directory (or folder) ~/www
and both it and all directories above it must be world executable.
That would be your home directory essentially. Files in your
~/www that you want people to be able to access via the
web must be world readable and the start page should be called
index.php (although older style start pages of
index.html
or
Welcome.html will get used in the absence of
index.php).
There are various College policies and recommendations on web pages.
(Section added 20/11/2011.)
Perhaps the most convenient way (for relatively occasional
formulae in a document) is to use MathJax, which is installed
on our web server.
If you include
<script src="/MathJax/MathJax.js" type="text/javascript">
MathJax.Hub.Config({
config: ["MMLorHTML.js"],
extensions: ["tex2jax.js"],
jax: ["input/TeX"],
tex2jax: {inlineMath: [["$","$"],["\\(","\\)"]]}
});
</script>
in the header section of your html document, it will work to
put things like $\int \sin \theta \, d\theta$
in hour html code (and the display should be $\int \sin \theta \, d\theta$).
There are also programs that take a whole LaTeX source
file and convert it to html (like tex4ht, tth
or
latex2html (but perhaps you wll find it easier to use
pdflatex to make a pdf file, install that on your
site with a link to it in a suitable place).
(Section added 20/11/2011.)
Yes - you should be able to pick up your mail using
pop3.maths.tcd.ie as your pop server and
your maths username and password.
Alternatively (and probably better) use
imap.maths.tcd.ie as your imap server (and maths username + password).
It is now (Feb 2013) possible to send your mail through maths while
not logged in to a mathe compuer, using
your maths username and password. You should set your smtp server
to smtp.maths.tcd.ie and to use port 587. This should
work happily with Thunderbird or Microsoft Outlook, for instance.
We have a web interface at webmail.maths.tcd.ie.
We hope to upgrade that to a newer version (fairly) soon!
(02/2013).
If you are sending mail from home you will have to have set an SMTP server. For sending machines outside Maths, see above instructions, or you may be able to send using the smtp server of your ISP.
The Maths Department mail server does not accept mail from computers with invalid or incomplete DNS entries. A DNS entry is a mapping from a name such as "salmon.maths.tcd.ie" to an IP address - 134.226.81.11 in this case. In other words if I do "nslookup salmon.maths.tcd.ie" I should get 134.226.81.11. This is a forward lookup. If I do "nslookup 134.226.81.11" I should get back salmon.maths.tcd.ie. This is known as the reverse lookup.
Almost all computers have the forward lookup configured correctly. Unfortunately some do not have the reverse lookup correctly configured.
We have never accepted mail from hosts with incomplete DNS records - this policy greatly reduces the volume of spam we receive. However, until recently some email from hosts with bad DNS records was relayed to us from the main Trinity College mailserver - which did accept such mail. Now though, they too have tightened their policy and are refusing such mail. This means that the backdoor has closed, and you may have stopped receiving email from certain addresses.
The correct solution is for the DNS of your friend/colleague's mailserver to be corrected. They may need to contact their System Administrator or their ISP. Feel free to forward this explanation onwards.
The Check DNS web page will perform a quick test of the DNS for your computer.
getputdir for get/put folders or
freddir for individual disk space. This provides and interface
like ftp. You can say cd, dir,
get and put. Typing in help gives a list of
commands. Say quit to finish.
You can set your college username with issname.
(Need some student to check if this is still working! (11/2011)
Email ops please.)
locate filename, which will list all files of name
filename on all the machines. This list is built
every Friday, so the file must have been there last Friday to be
listed.
Sorry, need to set something up for usb sticks, but it is not there yet (11/2011)
Thanks to Christoph Adam for this.
You will also need to know the name of the printer you are printing
to. They are named laser14, laser15, etc
according to the room in which they are in. In the following examples
I will use laser?? as the name of the printer.
lpr -Plaser?? filename. You can produce a nicer output
using the a2ps command - for example:
a2ps -Plaser?? filename.
.ps.
You can print them using the command
lpr -Plaser?? filename.ps. However you can
not use a2ps on them! There are some nifty things
you can do with psnup and psselect and
friends.
.tex file you first must make a
.dvi file using the command latex file.tex
or tex file.tex. Once you have your .dvi
file you can print it using the command
dvips -Plaser?? file.dvi.
To print in netscape choose "Print" in the "File" menu. A box
will pop up. Find where it says "Print To:" and click the diamond
to the left of "Printer". Then put the command
lpr -Plaser?? in the print command box. Finally hit
the "Print" button at the bottom of the box.
Note, If you are looking at a page in netscape which uses frames, then you should click on the frame you want to print in advance.
lpr -Plaser?? in the box to the right of "Print to".
Hit the OK button.
lpr -Plaser??. Click "OK".
convert can be quite useful. You can say
convert file.gif file.ps and then print
file.ps. Remember to delete file.ps
afterwards!
Some printers now have duplex units installed, which allow printing to both sides of a sheet of paper. Selecting whether or not to print in duplex is accomplished via selecting the correct printer queue.
In public computer rooms, the default queues (eg laser??)
are set up for duplex. If you need to print in simplex, you should
add an "s" to the end of the printer name
(for example lpr -Plaser??s)
Printers for staff are more commonly left as simplex by default.
Therefore, to print in duplex from these, you should select (for
example) lpr -Pwr06d.
Finally, for all printers with duplex units, in order to print
landscape-orientated pages (for example, those produced by
a2ps) properly in duplex, you should add an "l"
onto the name of the printer (for example,
lpr -Plaser??l).
hogs .
If you are on this list it probably means that you need to delete old files
and mail 'cos you are using more than your fair share of disk space.
We have hints on how to clean up.
myscript.cgi.
On our system we use the /www/common-cgi directory
for users CGI programs. You can just copy your program into that
directory, and then the URL for the script will be
http://www.maths.tcd.ie/common-cgi/myscript.cgi.
~/www/.htaccess. This file
should contain the lines:
Action php-script /common-cgi/php4
AddHandler php-script .php