4 Telescope Control & Data Acquisition Computers
4.1 INTRODUCTION
There are five "user" computers at the 2.4-meter telescope (in addition to special-funtion computers described in later sections of the manual):
All of the computers are networked together, with the raw data disks shared among the computers to provide direct access to the data from any workstation.
Summary:
All computers share a networked PostScript laser printer and their main home and data disks.
In addition, there are network ports available for connecting a laptop computer to the network as a guest machine. Details are given in a separate document available at MDM. We provide DHCP services at 10MB thru 1Gb speeds. Power users can mount the home and data disks on the mountain machines readonly using SAMBA with the standard username and special SAMBA password written on the white board. A short-range wireless network (802.11b/g protocol) is also available in the common areas at the 2.4m and 1.3m telescopes for wireless-equipped laptops.
All computers can also communicate via the mountain network with their opposite numbers at the 1.3 m McGraw-Hill Telescope: mcgraw, tambora, hill, and etna.
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 serious storm or a hardware failure.
With the exception of the monitor and keyboard, the sparcstation computers are located in the computer room racks. Open the rear cabinet doors to gain access to the power switches located on the back of the boxes. The box for agung sits in the computer rack next to vesuvius.The power switch is on the front panel.
To start the machine(s) go through the following sequence:
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 (krakatoa):
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 hiltner. Each program has a separate command window. This section contains all the information you need to control the telescope (xtcs), MIS box (xmis) and the old autoguider (xguider). 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 (hiltner), there is no need to log on. Skip this section. Otherwise, hit the Enter key and the login prompt will appear.
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:
| /home/hiltner/obs24m for hiltner |
| /home/krakatoa/obs24m for krakatoa |
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/hiltner/obs24m <cr> go to hiltner's data scratch area
cd /data/krakatoa/obs24m <cr> go to krakatoa's data storage area
Raw data for various instrument are written to data directories as follows:
CCDS and TIFKAM: /lhome/data on hiltnerAll of these disks are visible from hiltner and agung, so you can easily examine your data with IRAF or whatever. Note, however, that the old Sparcstation, krakatoa, is very slow, so it is best to copy raw data from krakatoa onto hiltner or agung before using IRAF.
CCD Cameras (ccdcom): /data/krakatoa/obs24m
MDM8K (detcom): /data/vesuvius/obs24m
4.3.3 Disk storage space
To find out how much disk space is used type the command df -h in a hiltner window. The last three columns of the table report the remaining available space, the used percentage of the disk capacity, and the disk identification. You can also use the KDiskFree tool on hiltner or agung to monitor disk usage graphically in real time.
We advise that you make a daily backup of your data to tape. DVD drive is available on agung and there is a DVD drive on hiltner. Observers with USB2 disk drives can plug in these to the front jacks on agung for another storage option.
4.3.4 Starting the Telescope Control Software
The TCS system is controlled from hiltner using the xtcs program. It is launched by selecting "xtcs" from "<Telescope Control>" menu on the X-windows desktop.
If you are using one of the MDM facility CCD cameras (except MDM8K), 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>" desktop menu.
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 hiltner 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 obs24m 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.
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).
4.4 SOME USEFUL INFO
4.4.1 Internet access
MDM has regular access to the Internet through a T1 link making it possible to ssh or scp to a machine at your home institution or elsewhere.
4.4.2 Storing data on DVD
Blank DVD+R disks are available on the mountain, though stocks are small. We recommend that you use only data-quality DVD+R disks (DVD-R also works, but avoid DVD-RW/+RW media as they have proven unreliable).For writing DVDs, put a blank disk into the DVD drive (data-quality DVD+R or DVD-R media work best), and then launch the k3b program on agung. The k3b program uses a standard drag-and-drop interface to let you build up a set of files to burn onto DVD, then burn the disk.
We recommend burning data onto disk at one time, rather than using so-called "open" disk formats which are prone to failure leading to loss of data. DVD media are cheap, so don't worry about not filling up an entire 4Gb disk at one time. We also recommend burning backup copies before you leave.
4.5 QUICK LOOK AND DATA REDUCTION
hiltner and agung have the latest versions of XVista (v7.x), IRAF 2.12, SAOimage ds9 (works on 24-bit displays, unlike XImTool), etc. All are familiar tools and are extensively documented.
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