4 Telescope Control & Data Acquisition Computers
There are four "user" computers at the 1.3-meter telescope (in addition to special-function computers described in later sections of the manual):
All of the computers are networked together, with the raw data disks shared among the three computers to provide direct access to the data. The raw data disk on tambora is called /data/tambora/obs13m, and has a capacity of 17.8 Gbytes. The raw data disk on etna is called /data/etna/visitor, and has a capacity of approximately 70 Gbytes.
The data-acquisition computers, tambora and etna, handle the real-time data-acquisition tasks and raw data storage that must proceed with minimal interruption. As such, neither of these computers has data-analysis software installed (except minimal packages only for engineering purposes). To ensure uninterrupted data-acquisition, the observer works with mcgraw, where they can control all aspects of data-taking, instrument setup, and telescope control. Most of an observer's run is spent sitting in front of mcgraw.
Fast Linux computers,mcgraw main station and hill, used as a second workstation dedicated to data-reduction. The Linux boxes are new, and have recently been re-configured (during the Summer 2005 shutdown period) with new hard drives and updated programs. Their performance is greatly improved, and they are now capable of handling most data-reduction tasks more quickly than the old Sparcstations.
All four computers share a network PostScript laser printer (both single and double sided black and white only) and share the raw data disks.
In addition, there are network ports available for connecting a laptop computer (Windows or Linux) to the network as a guest machine. Details are given in a separate document available at MDM. We provide both fixed-IP addresses and DHCP services at 100MB wire speeds. There is also wireless. You will need to have an ethernet card with a 10BaseT (RJ45) connector or wireless already installed in your laptop; MDM has none to provide.
All four computers can also communicate via the mountain network (via ssh and scp) with their opposite numbers at the 2.4-m Telescope: hiltner, krakatoa, agung, and vesuvius.
4.2 Basic Operating Instructions
4.2.1 Turning the machines on
Under normal circumstances the computers and their peripheral devices are left powered on at all times. The only time an observer will need to power up the machines from a cold start will be after a thunder storm or a hardware failure.
With the exception of the monitor and keyboard, the Linux computers are located in the computer room racks and the power switches are on the front of the computers. Open the rear cabinet for tambora to gain access to the power switch for tambora located on the back of the box.
To start the machine(s) go through the following sequence:
Of the four computers, etna will take the longest time to boot (~3 minutes). In general, unless you are using the MDM8K camera, etna should be turned off to conserve power. You should never have to login to the tambora or etna consoles except for emergency shutdowns in the event of lightning or severe weather.
4.2.2 Re-booting from a computer "crash"
Occasionally you will need to recover from a crashed or hung computer. Try to logout in the usual manner. If this fails try to issue Control-C a few times to see if you can get a response. If the system is still hung, reboot it as follows:
Sparcstation Reboot (tambora) tambora's keyboard is in the computer rack:
Type b (boot), c (continue), or n (new command mode) >
4.2.3 Turning the machines off
Leave the machines on unless there is bad lightning in the area. If you need to shut them down, please follow this procedure: Linux and Sun Workstations.
Caution - If you are cycling power on a computer (turning it off then back on again), always count slowly to 10 between "off" and "on" to prevent possible hardware damage (you need to give disks time to spin down, and various electrical systems to discharge).
4.3 The Telescope Control Computer
The telescope and MIS box can be controlled remotely using programs running on mcgraw. Each program has a separate command window. This section contains all the information you need to control the telescope (xtcs) and MIS box (xmis). The new PC autoguider cannot yet be remotely operated from the observer's workstation.
4.3.1 Logging on
The computers have a screen blank feature to stop image burn-in on the monitor. The screen goes blank if there is no activity after a certain period. Move the mouse or press any key (e.g. a Shift key) to activate the monitor.
If the windows are operating on the data acquisition computer (mcgraw), there is no need to log on. Skip this section. Otherwise, hit the Enter key and the login prompt will appear.
Support personnel will usually set up the telescope for a new
observer or after an instrument change. Observers should not attempt to
run the setup procedures unless specifically instructed to do so (e.g.,
over the phone while handling a late-night problem).
4.3.2 Directory structure
The computer is split into directories, analogous to different folders in a filing cabinet. These directories contain sub- directories and individual files. The "home" directory, which is where you will reside when bringing up a new window is:
|/lhome/obs13m for mcgraw|
|/home/tambora/obs13m for tambora|
You can find out what is in a directory with the command ls.
To change from one directory to another use the command cd, for example:
cd <cr> (go back to the home directory)
cd /data/mcgraw <cr> go to mcgraw's data area
cd /data/tambora/obs13m <cr> go to tambora's data storage area
Note that raw data for ccdcom (except the MDM8K camera) are written to /data/tambora/obs13m, which disk is mounted by both mcgraw and hill. tambora has a number of real-time functions associated with data acquisition that can be interrupted by attempting to also run IRAF or other programs, hence there are no copies of IRAF or other data analysis programs on tambora. CCDS and TIFKAM data is written to mcgraw.
You must change to the desired directory each time you bring up a new window. To find out where you currently reside issue the command pwd (print working directory).
4.3.3 Disk storage space
To find out how much disk space is used type the command df in a mcgraw window. The last three columns of the table report the remaining available space (kbytes), the used percentage of the disk capacity, and the disk identification.
We advise that you make a daily backup of your data to DVD. There is a DVD drive on hill.
4.3.4 Starting the Telescope Control Software
The TCS system is controlled from mcgraw using the MDM 1.3m TCS program. This can be started by the preferred way by putting the mouse cursor on the desktop ("background") screen, hold down the left-hand button and select MDM 1.3m TCS from the "<Telescope Control>" menu.
The MDM 1.3m TCS GUI window will appear on the desktop.
If you are using one of the MDM CCD cameras (but not the MDM8K camera), or one of the OSU instruments (CCDS or TIFKAM), you also need to start the xmis program which controls the Multiple Instrument System or MIS. Do this by selecting xmis from the "<Telescope Control>" menu.The xmis window will appear on the desktop.
If you are using the MDM8K camera, it has its own filter wheel system and the MIS will not be mounted on the telescope.
4.3.5 Restarting individual windows
You might need to re-start an individual window if it is accidentally destroyed (!) or if it crashes. Remember that the telescope control, MIS and guider programs must be run from a mcgraw console window. Also remember that windows (and especially icons) can be hidden under other windows.
If the window hangs do the following:
If you think that the window has genuinely crashed or is absent, enter the command jobs. If the window name appears as a stopped job, kill it with the command kill %n where n is the stopped job number displayed to the left of the job name. Also issue the command ps -x to list all the processes that belong to the visitor user. If the window name appears in the list, kill the process with the command kill nnnn (or kill -9 nnnn) where nnnn is the process number. Repeat the ps -x command to check that the process was indeed destroyed.
Once you are sure that the window is not running you can restart it by typing its name followed by an & .
Keeping the number of extraneous windows to a minimum will increase the efficiency of the computer. Error messages are reported in the console window, which should not be destroyed. It is usually kept as an icon labeled "Console" in the upper left-hand corner of the screen (near the virtual desktop panel).
4.3.6 The Mouse Buttons
This section used to be an extended primer on how to use a window-based computer, back in the days when "dumb terminals" were all the rage. We now assume that anybody who has not used a windows based computer probably has no business being here by themselves, and better catch up with the 21st century or go extinct...
Everybody sets up their windows differently, but a few basic styles have begun to converge. Because the observing console also uses programs like ds9 or ximtool to display images, we have purposely kept the number of fancy color buttons to a minimum since these interfere with the image display.
The mouse menus are kept as simple as possible, and are the same on all of the MDM computers (allowing, of course, for features not available on all machines).
The three mouse buttons are assigned as follows:
A couple of special "hot" keys are also available on the keyboard:
Additional window operations:
4.4 SOME USEFUL INFO
4.4.1 Internet Access
MDM has regular access to the Internet through a T-1 line (1.5 Mbit/s) that is connected through the Kitt Peak mountain network, making it possible to ssh or scp to a machine at your home institution or elsewhere. Due to variable network usage on Kitt Peak, actual data transmission rates can be significantly lower than the theoretical maximum. In addition, you should be aware that MDM is billed a significant amount based on its actual fraction of the total Kitt Peak network traffic. For these reasons, the Internet is suitable only for transfer of small data files, but it can be quite satisfactory for checking weather reports and satellite images, and otherwise killing time on cloudy nights.
4.4.2 Storing data on DVD on hillTo write all of the FITS files to DVD, load a DVD on hills DVD drive carrier and follow the MDM Info Sheets.
Other useful commands:
Which kind of DVD should you use? buy only
DATA QUALITY DVD+R or DVD-R
4.5 Quick Look and Data Reduction
Mcgraw and hill have the latest versions of XVista
(v6.0.1), IRAF 2.11.x, XImTool, SAOimage ds9 (The old SAOimage is no
longer supported, ds9 is a way better program by a long ways, and works
like SAOimage, only better). All have extensive online help files.
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