Methods for Remote Access to ursa.astro.umd.edu

 

 

A manual for the students of ASTR310

 

 

By Jessica Webbon

 

 

 

 

 

 

 

Table of Contents

 

Introduction…………………………………………… 3

Remote Access from the Astronomy Lab………….4-6

            lab hours………………………………………...4

            tools……………………………………………...4

            steps…………………………………………...4-6

            tips……………………………………………….6

Remote Access from Campus Unix Labs………….7-9

            lab hours………………………………………...7

            tools……………………………………………...7

            steps…………………………………………...7-9

Remote Access from Campus Dorm Room…….10-13

            X-WIN32 installation…………………………10

            information about demo version……………10

            tools…………………………………………….10

            steps………………………………………...11-12

            steps for finding your computer’s name..12-13

            tips……………………………………………...13

Additional Resources…………………………………14

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Introduction

 

            Observational Astronomy, or ASTR310, is taught by Professor Veilleux in the fall of each school year and requires you to complete four research projects, comprising 40% of your grade. The projects will involve the use of the Interactive Data Language (IDL) to analyze the data, working on the computer ursa.astro.umd.edu (referred to simply as ursa from this point on).

            Ursa is an Astronomy Department computer, but it is accessed by remote, which means that no one works on ursa itself, but students use the computer by logging into it from a different computer. The method used to log into ursa varies depending on the computer from which you are logging in.

            This manual will guide you though the basics of logging onto ursa from the Astronomy Department Computer Lab, from other UNIX labs on campus, and from a campus dorm room. The ability to access ursa remotely will allow you to complete your lab in a timely manner by removing the time constraints of the Astronomy Department Computer Lab.

 

 

 

 

 

 

 

 

Remote Access from the Astronomy Computer Lab

 

            The Astronomy Computer Lab is on the first floor of the old wing of the Computer and Space Sciences Building. Professor Veilleux will take the class to the lab and demonstrate the following method.

 

LAB HOURS

·          The computer lab is usually open by 10am.

·          The lab can be opened earlier upon request.

·          The lab closes at 4:30pm daily.

·          The lab may be closed much of the day for classes. (Consult the class schedule on the lab door for specific class times.)

 

TOOLS

·          Research project and associated notes

·          IDL reference package

·          Astronomy Computer Lab computer station

·          Ursa username and password

 

STEPS

1.      Single click “˙ Start” in the lower left corner of the screen.

2.      Click “Programs.”

3.      Click “X-Win32 5.1.”

4.      Click “X-Win32,” which is next to a blue X as in Figure 1.

Figure 1: Screen appearance when starting X-Win.

 

5.      Select “Evaluation.”

6.      Select “Continue.”

7.      Look in the tool tray in the bottom right corner of the screen. A small blue X should appear there. Right click it (click it once with the right mouse button).

8.      Left click “Sessions.”

9.      Click the option listed as “ursa.astro.umd.edu” as in Figure 2. If this option is not listed, contact the professor.

 

Figure 2: Screen appearance when starting ursa session.

10.  At the prompt, enter your username and password (these were given to you by the Professor Veilleux. If you do not have them, see him).

11.  You are now logged into ursa. Proceed with your analysis. Anything you print will be printed in the Astronomy Computer Lab.

12.  Type exit to log out.

13.  To close X-Win right click the blue X on the bottom right of your screen and click “Close.”

 

TIPS

·          Ursa polls the lab computer many times a second to find out if you clicked a mouse button. If you click at a time when ursa is not polling the lab computer, ursa will not respond to the click. You may have to hold down the mouse button longer than normal to get a response.

·          If five or more people are logged into ursa from the Astronomy Computer Lab doing data analysis, ursa may be overloaded. It will either run very slowly or cut off your connection. Follow the steps above to log back in. Beware that you may lose your work during these times if you do not save frequently.

·          If there is an X-Win icon (a blue X) on the desktop, you can replace steps 1 though 4 by double clicking it.

·          If you have any difficulties, Professor Veilleux’s office is CSS 0223. Contact him.

 

 

 

 

 

 

 

Remote Access from Campus UNIX Computer Labs

 

            Ursa can be accessed from any of the campus computer labs that have UNIX computers. Table 1 will help you choose which lab to work in.

 

LAB HOURS

Location

Mon-Thu

Friday

Saturday

Sunday

1136 LeFrak

10am-9pm

12pm-5pm

11am-4pm

Closed

1442 AVW

8am-12am

8am-12am

8am-12am

7am-12am

1120 AVW

24 hours

24 hours

24 hours

24 hours

4352 CSS

8am-11pm

8am-5pm

Closed

Closed

2304F Math

8am-12pm

8am-8pm

10am-8pm

12pm-12am

PG II

24 hours

24 hours

24 hours

24 hours

0111 Worcester

24 hours

24 hours

24 hours

24 hours

Table 1: UNIX lab locations and hours.

 

TOOLS

·          Research project and associated notes

·          IDL reference package

·          UNIX workstation

·          WAM username and password

·          Ursa username and password

 

STEPS

1.      Enter your username and password in the prompts and hit enter.

2.      Click “Continue.”

3.      You will now see three windows. The one called “xconsole” displays the lab computer’s name as in Figure 3. In one of the others, type: xhost ursa.astro.umd.edu and hit enter as in Figure 4.

 

 

 

Figure 3: Lab computer name.

 

 

Figure 4: The xhost command.

 

4.      In the remaining window, type the following: rlogin –l <ursa username> ursa.astro.umd.edu as in Figure 5. Replace <ursa username> with your ursa username. The professor gave this to you along with your ursa password. If you do not have this information, see Professor Veilleux. Note that, once this step is complete, the title on the window will change from the name of your lab computer to ursa. Ignore all warning statements.

5.      In this same window, type: setenv DISPLAY <lab computer name>:0.0 as in Figure 5. Replace <lab computer name> with the computer name appearing in the “xconsole” window.

 

Figure 5: The rlogon and setenv command.

 

6.      You are now logged into ursa. Proceed with your analysis in the ursa window. You can type xterm & in this window if you need another ursa window.

7.      When you are done, type exit in the ursa window.

8.      To log out of the lab computer, click on “logout” in the “Special” menu, which you will see towards the upper right of the screen.

 

TIPS

·          You may print in the ursa window, but your paper will come out of the printer in the Astronomy Computer Lab.

·          If your username on ursa is identical to your WAM username, you can (but do not have to) replace the rlogin –l <ursa username> ursa.astro.umd.edu command with rlogin ursa.astro.umd.edu.

·          If you have any difficulties, ask the person at the help desk.

 

 

 

 

Remote Access from Campus Dorm Room

 

            This is the most complicated and most useful of the remote access methods. You will have to download a free version of X-Win32 to proceed.

 

X-WIN32 INSTALLATION

1.      Check that you have 9 MB of free memory and an Internet connection.

2.      Go to http://www.starnet.com.

3.      Click on “Products and Downloads.”

4.      Click on “Demo Download.”

5.      Click on “Available for Download” under Free Evaluation.

6.      Follow the web site’s download instructions.

 

INFORMATION ABOUT DEMO VERSION

            Because it is free, you will be downloading the demo version of X-Win32. You have unlimited use of your program, but it will close automatically every two hours. You can reopen it and repeat the following remote access steps in order to log back in to ursa.

 

TOOLS

·          Windows Personal Computer (PC)

·          Campus network connection through dorm room

·          Your computer’s name (you chose this when you originally put your computer on the campus network. If you do not remember what it is, there are steps below that you can follow to determine it).

·          Research project and associated notes

·          IDL reference package

·          Ursa username and password

 

 

STEPS

1.      You have downloaded X-Win32. Follow steps 1 through 6 in the Astronomy Computer Lab directions.

2.      Single click “˙ Start” a second time.

3.      Single click “Run.”

4.      In the box entitled “Open:”, type telnet ursa.astro.umd.edu and hit “OK.” The telnet program comes with Windows. See Figure 6.

 

Figure 6: Run window.

 

5.      A telnet window will ask you for your ursa username and password. Enter these. If you do not have these, contact Professor Veilleux.

6.      In the telnet window, type setenv DISPLAY <lab computer name>:0.0. Replace <lab computer name> with your computer’s name. See Figure 7.

 

Figure 7: Telnet window with setenv command

 

7.      Type xterm & in the telnet window. X-Win32 allows telnet to open up a window. Work in this window, not in telnet, although you can type xterm & in any window, any time you want a new window.

8.      Type IDL in any “xterm” window to begin your lab analysis.

9.      When you are finished your lab session, type exit in the telnet window.

10.  To close X-Win, right click the blue X on the bottom right of your screen and click ‘Close.”

 

STEPS FOR FINDING YOUR COMPUTER’S NAME

1.      Single click “˙ Start” in the lower left corner of the screen.

2.      Click “Settings.”

3.      Click “Control Panel.”

4.      Double click “Network.”

5.      Click the “Identification” tab.

6.      Next to “computer name” is your computer’s main name. Append “.student.umd.edu” to get your computer’s full name.

 

 

Figure 8: Network menu.

 

TIPS

·          Do not attempt to change X-Win32’s default settings, or the above process may not work.

·          You can still print with this method, but your paper will be printed in the Astronomy Computer Lab. Pick it up soon.

·          For X-Win problems, contact the user support listed on http://www.starnet.com.

 

 

 

 

 

 

 

Additional Resources

 

Office of Information Technology. “General Lab Information.” Where to Go. http://www.oit.umd.edu/wheretogo/seeTable.cfm (April 26, 2002).

 

Robbins, Arnold. Unix in a Nutshell. Sebastopol: O’Reilly and Associates, 1999.

 

StarNet Communications. “X-Win32.” StarNet Communications Home Page. http://www.starnet.com (April 26, 2002).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cover Photo: The Ring Nebula. Jessica Webbon and Alex Etter. 20-inch Cassegrain reflecting telescope. University of Maryland Observatory.