Frequently Asked Questions
Version 3.2
September 2001
Contents
Introduction
OPUS Installation
OPUS Servers
OPUS Sample Pipeline
OPUS Process Manager
OPUS Applications
OPUS Process Resource Files
OPUS Path files
OPUS Observation Manager
OPUS Tools
OPUS Upgrade Information
Glossary
E-mail Help
What if I can't find my question in this FAQ?
Introduction
What is OPUS?
What is included in the OPUS System?
What are the OPUS "Managers"?
What is not included in the distribution?
What does the OPUS Sample Pipeline demonstrate?
Why can't I just use a shell script to tie my applications together?
Why are multiple instances of applications important?
How many steps can there be in the pipeline?
What are paths?
How does OPUS work?
Wasn't OPUS developed for the HST project?
Isn't OPUS too elaborate for a small mission?
OPUS Installation
What are the system requirements for the OPUS system?
How much disk space is required to install the OPUS system?
Can I run OPUS on a network of computers?
Does OPUS require special privileges to run?
How do I obtain the OPUS system?
Do I have to put the OPUS distribution in a specially named directory?
How do I install the OPUS distribution?
What do I do if the installation fails?
How do I uninstall the OPUS distribution?
How do I configure my accounts to run OPUS?
What is the OPUS directory structure?
What environment variables are required?
How do I determine whether OPUS works on my system?
Can I run the sample pipeline on a network of mixed Unix types?
How do I upgrade my version of the OPUS distribution to v3.2?
What, exactly, does the upgrade process do?
OPUS Managers
How do I install the OPUS Java Managers?
What platforms can I run the managers on?
How do I run the installers?
What choices do I have?
Finally, how do I run the installed managers?
OPUS Servers
What are the OPUS servers?
What is meant by beta products?
When must I use the servers?
What are the advantages of running in CORBA mode?
What are some possible disadvantages?
Do I need special privileges to run the servers?
How do I start and stop them?
Why do I get a "Permission denied" error when I try to start the servers?
What happens if a server crashes?
What do I have to do before manually restarting the servers after a problem?
Are the servers secure?
What enhancements can I expect to the servers in the future?
Sample Pipeline
What does the sample pipeline do?
How do I run the sample pipeline?
How much disk space do I need to run the sample pipeline?
Do I need a database to run the sample pipeline?
Can I use the FITS files to do science?
How does OPUS make things easier?
What do I have to do to rerun the sample pipeline?
What does it mean if a process is marked ABSENT on the PMG display, and what do I do?
Why do some GIF images fail the KW step in the sample pipeline?
How do I determine if the process status entry is created?
How do I determine if the observation status entries are created?
In what order are datasets processed in the pipeline?
Can I run more than one conversion process (
g2f
) in the pipeline?
How do I distribute processes over different machines?
How do I bring up multiple instances of the pipeline?
How do I determine if one of the processes has crashed?
How do I know when the processing is complete?
How do I turn the pipeline off?
What happens if I run out of disk space?
I can't find the output for this sample pipeline!
How do I display the results to verify the operation?
Why are the images in the FITS files monochromatic?
How do I verify that the FITS files comply with the standard?
Is there an easy way to list the keywords in a FITS file?
Can OPUS do parallel processing?
How do you make a process wait for the completion of two tasks?
How can I run parallel pipelines (paths)?
OPUS Process Manager
What is the PMG?
Do I need any software not provided on the OPUS CD to run the PMG?
How do I start the Process Manager?
What's the password dialog for?
What is a process status entry?
Can I modify the structure of a process status entry?
How do I tell the PMG which paths to monitor?
How do I start up a process?
How do I remove a pending task?
How then do I actually start the process?
How do I terminate a running process?
Can I suspend a specific process in the pipeline?
How do I resume a suspended process?
How do I bring all processes down?
My Selections are disappearing!
What is a pipeline?
How do I define a pipeline?
How do I create a pipeline file?
Can I save the pipeline definition?
How do I load a saved pipeline definition?
How do I start the pipeline?
OK. I did that, but nothing happened! Now what?
How do I remove a path from my PMG display?
How do I remove a column from the PMG?
Can I add a path to the PMG display?
How do I get help to work?
How do I know if a task exits abnormally?
What do I do if a process exits abnormally?
How do I view the log file for a particular process?
How do I select a new set of nodes?
How do I save my preferences?
What is in the PMG.ini file?
How can I restrict the number of processes in a pipeline?
Can I add functionality to the managers?
OPUS Applications
What are the advantages of using OPUS?
What kind of processes can be run in the pipeline?
Can a script read from STDIN (standard input)?
Can I use command line arguments for my tasks?
How are the values of environment variables set?
What is the difference between an external and an internal poller?
How do I add a processing step to a pipeline?
Are there any limitations on naming a new task?
What are some of the common gotchas I should beware of when I write my OPUS tasks?
What kind of message reporting does OPUS provide?
Process Resource Files
What is a process resource file?
What is contained in a process resource file?
What's an easy way to view the process resource file?
What is the complete format of a line in the process resource file?
What are the minimum keywords required in a process resource file?
Which process resource file keywords are reserved or have specific uses?
Where will I find process resource files in the OPUS directory tree?
What types of pipeline triggers can be set up in a process resource file?
How do I set up a process with an OSF trigger?
How do I set up a process to trigger on the existence of a certain file?
How do I set up a relative time trigger?
How do I set up a process to trigger once a day?
How can I use the exit status of a process to trigger pipeline actions?
How can process resource keyword values be obtained by a script?
Can keyword values be obtained from files other than the process resource file?
What are the differences between path files and process resource files?
Can resource file parameters refer to a specific path?
How do you decide whether to put a keyword value in a path file or in a process resource file?
Can I give a keyword different values for the same process running in different paths?
Are process resource file keyword names case sensitive?
Can OPUS protect against running out of disk space?
So what do I do if a process is in this "iowait" state?
OPUS Path files
What is a path?
Where do I find the path files in the OPUS directory tree?
How do I find out what directories are used in a path?
What are the rules for making a path file?
Are things other than directories in a path file?
Do the path file variables supersede process resource file variables?
How do path names get translated?
Can one pipeline feed data into another pipeline?
How does a task "inquire" for a path file value?
What keywords are required in the path file?
Observation Manager
What are observations?
What is the OMG?
Do I need any software not provided on the OPUS CD to run the OMG?
How do I start the Observation Manager?
What is the password dialog for?
What happens if I am properly authorized?
How do I select a path?
Ugly! How do I get rid of the dots?
How can I subdivide a display field?
How do I save my preferences?
Does the OMG support the OAPI?
What is the difference between managing and monitoring a path?
What is an Observation Status File (OSF)?
Can I modify how an Observation Status File is structured?
How do I create an OSF?
How do I update an OSF?
How do I test for an OSF?
How do I read the time stamp on an Observation Status File?
Can I monitor more than one pipeline or path at a time?
Can I stop a specific observation from processing further?
How do I tell if an observation has encountered a processing problem?
Is there a way to determine the meaning of a status of an observation?
How do I change the status of one or more observations?
Can I change the frequency at which the display is updated?
Can I filter the types of OSFs that are displayed?
Can I copy part of the OSF listing to the system clipboard?
How do I change the colors used on the display?
What controls the order of the observations in the OMG?
Is there any limit on the length of observations "name"?
What is the pipeline stage file?
Glossary
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