How to use the school's computers

The school has a number of Linux workstations that may be used by faculty and students for teaching and research only! All machines are networked and can be accessed through ssh, sftp, browsers, etc., from anywhere on the Internet. The school has  dedicated Linux servers "math" for use by faculty & staff and  "mathpost" for use by graduate students only. Both servers can be used as web or compute servers. Other servers or small linux clusters are available for scientific computing. All major applications are installed on these servers. All Math graduate students have an account on "mathpost". Students may create their webpage on "mathpost". The webpage should contain information about teaching and research only.Please do not post private photoalbum etc.

Choosing a Password

When you login to your Linux account for the first time, you should change your default password (command: passwd). In general you should change your password frequently. Unfortunately, the process of choosing a secure (non-guessable) password is not a trivial matter. It is complicated by the sophisticated technology available to system "crackers".

The following list of DON'Ts are standard guidelines:

DO NOT use:

  • a password with less than six characters.
  • a word in any dictionary (English or otherwise!)
  • a misspelling or reversal of a dictionary word. (i.e. "raazab", which is "bazaar" spelled backwards)
  • your name, your login name, or a trivial variation thereof (e.g. If your name is John P. Smith, and your login name is "smith", the following passwords would be considered guessable: "SMITH", "jsmith", "jp", "smitty", "sm!th", etc.).
  • any proper name of people or places
  • a sequence of keys on a typewriter ("qwerty") or in the alphabet ("abc123)

DO use:

  • a password that is the first letters of each of the words in a phrase
  • a password that includes one or more digits or punctuation symbols
  • both upper and lower-case letters

One well constructed password might be:

"C!Wwbima?"

which came from the phrase, "Curious! Who would break into my account?", which uses all three of the above suggestions. This produces a random seeming password that you can remember. Of course, now that it's printed here, this example is not a good choice to use as your password.

Disk Space

The school does not currently enforce strict disk space quotas for our researchers. However, please be aware that you are sharing space on a disk partition with many other users. We ask that you please do not use so much space that others on the partition are not able to get work done. We may ask from time to time that users with files they no longer need on the system back them up and remove them.

It is also possible for one person to accidentally use up all of the free space on a disk. This can happen when a program crashes and dumps a very large core file, for instance. By typing the command "limit coredumpsize 3m" at the prompt or coredumps would be limited.

Using e-mail

The school offers support for ASU Gmail and exchange.

SSH : Remote workstation access

To connect from one workstation to another,please use SSH.

ssh "<-p port number>" "username"@"machinename"

or

ssh "<-oport=port number>" "username"@"machinename"

For example,to connect to mathpost.asu.edu as user "smith",

ssh -p 2200 smith@mathpost.asu.edu

or

ssh -oport=2200 smith@mathpost.asu.edu

SFTP : Secure File Transfer Protocol

If you want to transfer files or directories from one workstation to another,please use SFTP or the graphical interface gftp.Please make sure that,in gftp,the transfer protocol is set to ssh2. Also, make sure to use "<-oport=port number>" to specify the port number.

sftp -oport=2200 smith@mathpost.asu.edu

Remote display

The Remote display can be set by specifying the -X command.

ssh -X -oport=2200 smith@mathpost.asu.edu

MAC users please use:

ssh  -Y -p 2200 smith@mathpost.asu.edu