Physics Login Machines

PNCE-Unix Environment

Overview of PNCE-Unix Login Machines

Physics Computing Services maintains a small cluster of login machines to provide general Unix access to members of the Physics Department. At the time of this writing, the cluster consists of five machines, all of which answer to the generic hostname login.physics.umd.edu. These machines are all a subcluster of the campus Glue system, and so see the same filesystems, in particular, the same home directory as other Glue or PNCE-Unix systems. Details on the machines

These machines are available to anyone in the department. Among the resources they provide:

• Unix shell access via secure shell (ssh)
• Uploading/downloading files from AFS via secure file transfer (sftp) or secure copy (scp) protocols.
• access to your @physics.umd.edu email via pine.
• access to departmental or personal web pages (for editting, uploading via sftp or scp.
• access to assorted programs available in Glue or PNCE-Unix, e.g. Mathematica, MatLab.

Although it is expected that most uses of the system will be light-weight, users are allowed to engage in some brief CPU-intensive operations, such as compiling programs, short term interactive Mathematica sessions, or other short term programs. If your activity is likely to be CPU intensive for more than 5 or 10 minutes straight, you should consider using one of the departmental compute machines so as not to negatively impact the experience of other users. If excessive hogging of the CPU on these machines is noted, the offending processes will be terminated, and your access to this resource may be restricted.

To access these machines, you will need to use a secure protocol. For shell access from a PC, this is typically the F-Secure Secure Shell or other ssh type program. Once the application is started, you will need to tell it to ssh to a login machine. The procedure depends on the application, but usually is by clicking on a button or finding a drop-down menu item called something like Connections or Quick Connect. This should prompt you for a machine or host name, enter login.physics.umd.edu. It will also prompt for an username; this is the SOMETHING in your SOMETHING@physics.umd.edu, SOMETHING@glue.umd.edu, or SOMETHING@umd.edu email address. After you provide that information, it will request a password, this is the same password as you use for your @physics.umd.edu or @glue.umd.edu email account. (Your @umd.edu email may be on another system and so the password might or might not be the same.)

To copy files between your PC and these machines (or any of the PNCE-Unix AFS file systems, all of which are accessible from these machines), you need to use a secure protocol for file transfer, either sftp or scp. Most PCs in the department should have something like F-Secure File Transfer program on the system, and you can access the system using similar procedure to described for the GUI ssh client.

PC users can also use the command line putty application to access these systems, using something like

Unix users can use the standard ssh and scp utilities, e.g.

If you are not at a machine with the secure shell functionality, and cannot get it installed (i.e. you are visiting another institution and borrowing a machine), you may be able to use a java based ssh applet to login to these machines from a web browser. (You will be required to provide a PNCE-Unix or Glue username and password to download the java applet, and again when logging into the system.)