This page briefly describes how to access the CS department's Linux machines ``remotely'' -- i.e., how to use them if you are not sitting in front of them. For more details, or if anything described here does not work, talk to your instructor or send e-mail to the CSadmin address posted in the labs. (Suggestions for additions to this page are welcome; send to bmassing@cs.trinity.edu.)
The department's description of facilities has links to pages describing the department's various lab and listing the names and current status of available machines. Machines that show as ``up'' on the appropriate status page are available for remote access from other campus computers. (Note that the complete list at Status of CS Unix Machines also includes the names of research machines not available for general use.)
If you need access from off-campus, talk to your instructor or one of the CS admins.
At one time in the past, users were able to remotely log into one of the department's Linux machines using one of the standard Unix remote-login commands, telnet and rlogin. For security reasons, we now disallow this; you must use the newer and more secure command ssh.
To connect to remoteMachine, type ssh remoteMachine. For more information, read the man page for ssh (type man ssh). Normally ssh will prompt you for a password; you can find instructions for setting up password-less access in Using MPI on the CS Linux Machines.
Once you have logged in, you can execute any text-based program (ls, vi, etc.). Depending on how your local machine is set up, you may also be able to run programs with a graphical component (firefox, gvim, etc.). If you have trouble, first try re-executing the ssh command with the flag -X (e.g., ssh -X remoteMachine), and then ask for help.
To transfer files, you can use the command ftp or the newer and more secure command sftp. If you only need to transfer a single file, or a set of files easily referenced by a regular expression, scp may be more convenient and is just as secure. For example, the command scp remoteMachine:/full/*.txt . transfers a group of files matching the wildcard. For any of these commands, read the man page(s) for details.
At one time in the past, users were able to remotely log into one of the department's Linux machines using the standard Windows telnet program. For security reasons, we now disallow this; you must now use a program that supports the newer and more secure SSH connection protocol.
Probably the best (most complete) solution is Cygwin, which provides a Unix-like environment under Windows. It should be installed on all the CS Windows machines; when you click on its icon, you should get something that looks like a Linux terminal window, and you can execute the commands described above for accessing one Unix/Linux computer from another. Cygwin is free and available for download at http://www.cygwin.com.
If all you need is a terminal emulator (something that behaves like a terminal window and lets you execute text-only programs such as gcc and vi), we like the free program PuTTY. It should be installed on all of the CS department's Windows machines, and may be installed on other campus machines as well. It is also available for download at http://www.chiark.greenend.org.uk/~sgtatham/putty.html. It does not support programs with a graphical component (firefox, gvim, etc.); for that we recommend Cygwin, though there are other solutions (do a Web search for ``X server'' and ``Windows''). To use PuTTY, start it up, make sure the SSH radio button is selected, type the name of the machine you want to access into the ``Host name or IP address'' box, and click ``Open''. (You may need the full name, e.g., xena21.cs.trinity.edu). You should then get a terminal window prompting you for your username and password.
To transfer files, you should be able to access your Sol home directory from your Windows account by clicking ``Run'' and then typing \\sol.cs.trinity.edu.
For Mac OS X, starting the Terminal application gives you something very like a Linux terminal window, in which you can use most or all of the commands described previously for accessing one Unix/Linux system from another. The possible exception is connecting in a mode that supports running graphical programs; if the instructions above do not work, you may need to install additional packages; talk to your instructor or one of the admins.