Frequently Asked Questions

OpenSTA FAQ

Welcome to the Frequently Asked Questions section on the OpenSTA portal. You may get back to this page by clicking the OpenSTA logo at the top right of each page or by selecting FAQ in the main menu on the left.

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General Questions

• What is OpenSTA?
• Who is OpenSTA designed for?
• Where did OpenSTA come from?
• Is OpenSTA really free?
• Who are the people involved in OpenSTA?
• Where can I find out more about OpenSTA?
• How should parts of OpenSTA be referred to?
• Is OpenSTA easy and intuitive to use?
• What is a good place to start reading about Http?
• What is a good place to start reading about performance testing?

Getting and Installing OpenSTA

• What do I need to install OpenSTA? including what Operating Systems it installs on.
• What is the minimum hardware I can run OpenSTA on?
• Where do I obtain OpenSTA?
• What version should I download/install? including what the versions represent.
• How do I install OpenSTA?

Help and Support using OpenSTA

• Where can I get support for OpenSTA?
• I need support urgently, what should I do?
• Can I buy a ''commercial style'' support package?
• Where can I find information about the OpenSTA mailing lists? including how to subscribe and unsubscribe
• How can I easily search through all the publically accessible OpenSTA information? including mailing list archives
• What help is there for me to learn OpenSTA?
• Are there any Local OpenSTA User Groups?

Using OpenSTA

• Where can I obtain documentation about OpenSTA?
• What are the components making up OpenSTA?
• What hardware do I need for testing? i.e. how many virtual users are supported by my hardware?
• Can OpenSTA be used for functional/regression testing?
• Can the OpenSTA tools be used from the command line (in batch mode)?
• What OpenSTA key concepts and terminology will help me use it?
• Can I record/replay browser based file uploads?
• What database software does OpenSTA work with?

Recording

• How does recording work?
• How do I record a Web transaction(HTTP) for OpenSTA?
• What do I do if I have problems recording?
• I'm not able to record HTTPS traffic. How do I do this?
• How do I record through my own Proxy?
• How can I make a recording using a browser that the Modeler doesn't start? including browsers on remote machines
• Can I make a recording from a HTTP client that is not started by the OpenSTA Modeler? including other browsers and applications which are not browsers
• Can I record browser activity on a host that doesn't have OpenSTA installed?
• Can I insert custom timers whilst recording
• Why might the Modeler not start a browser for recording?
• What are these strange proxy settings in my browser and how did they get there?
• ScriptModeler seems to record hardcoded cookies instead of dynamic ones - what to to?
• What are the limitations of the OpenSTA recording mechanism?
• Why do my recordings all use HTTP/1.0 when I am using a modern HTTP/1.1 capable browser?

Scripting

• What is SCL?
• [How to Handle the situation when the requested page is not available?
• How do I use unprintable characters in SCL?
• How do I extract content from a HTML page to my script? OR How do I validate my results
• How do I make my Script log into my Web site with many different username/password combinations? OR MUTEX and data iterating example
• How do I synchronize my VU's at specific points? using semaphores
• How does the file handling in SCL work?
• How do I use SCL "file variables"?
• How do I create SCL variables using a Database?
• Where can I find example SCL code?
• How do I correctly handle http redirections in SCL? Handling response codes 30x
• How does OpenSTA handle URL-encoded session identifiers
• How do I improve the efficiency of my SCL?
• What HTTP specific commands does SCL have?
• How do I embed variables in strings in SCL?
• What does DOM, DOM Signatures and DOM Addressing mean?
• How do I define variables with regards to scope and manipulation?
• How do I model a script so that it can be run against more than one host?
• How does OpenSTA handle the DotNet ViewState?
• How does OpenSTA handle a Web Page that uses Struts?
• What happened to the REQUEST_TIMEOUT in older OpenSTA SCL scripts?

Test Configuration

• How do I add a Script or Collector to a Test?
• Why am I getting no ''Page Timers''? Or what are these Page Timers?
• Is there a better explanation for the ''introduce users in batches'' options?

Collectors

• What is a Collector?

SNMP

• What can an SNMP Collector do?
• I'm new to SNMP, what does this all mean?
• ?How do I make OpenSTA aware of a custom MIB?

NT/W2K Performance

• What can an NT Performance Collector do?
• I can't get an ''NT/W2K Performance'' working, what should I do?
• How do I access Performance Monitor Counters without admin rights on the server?
• Which Performance Monitor Counters should I use?

Playback

• What hardware do I need for testing? i.e. how many virtual users are supported by my hardware?
• What is a VU?
• I am getting errors in my script, what do I do now?
• My playback is successful (HTTP 200 OK) but the script isn't doing what I expect including my database isn't updated!
• How do I distribute my load generation across many machines?
• The script always uses the same cookie for every VU. What's wrong?
• During Playback, I experience Error 10048 "Address already in use". What's wrong?
• I'm getting "Request time out for VU ..." because my requests seem to take too long. Can I parameterize the time for a request timeout?
• How does OpenSTA display the pages during playback?
• Can a single playback machine simulate users appearing to come from different IPs?
• Can the VUs be made to playback as if they were operating over a bandwidth limited connection?
• Is there any System or OpenSTA specific tuning I can do to improve playback efficiency?
• I have problems establishing HTTPS connections during playback
• How do I make OpenSTA use URL-encoded session identifiers
• How does OpenSTA handle the DotNet ViewState?

Results

• Can I define my own custom timings to include in the Results?
• How can I do further analysis on the Results?
• What are the meanings of the graphs?
• What are these InjectorStatus messages at the end of the Test Error log
• How can I find the cause of errors?

Problems with OpenSTA

• How do I know if an error is due to OpenSTA or the Application Under Test?
• What extra runtime information (tracing) can be output to help finding problems?
• I've found a bug, what do I do?
• What are OpenSTA's known limitations?
• What are the known problems with the current release of OpenSTA?

Real meanings of error messages (and what to do about them)

• Commander GUI - Cannot Start the HTTP Modeler?
• Test Error Log: No data available for connection id?
• Test Error Log: InjectorStatusImpl: ... Could be TG stopped or completed?
• Test Error Log: Error 10048: ... one usage of each socket address?
• Test Error Log: Error 10060: ... connection attempt failed ... did not properly respond after a period of time.?
• Modeler/Test Audit Log: ... FAILED PROCESSING TOF ... : CECListVar::get_value
• Modeler/Test Audit Log: ... HTTPRESPONSE (HTML parser): unresolved variable for connection ...
• Modeler/Test Audit Log: ERROR: FAILED PROCESSING TOF RECORD FOR SCRIPT LINE ...
• Recorded Script: ... Unsupported protocol packet received : cannot continue - page will have failed to display during recording.

Developing OpenSTA and its future

• Where can I get the OpenSTA sources? Including other CVS hints
• What do I need to build OpenSTA?
• How do I build OpenSTA from the source?
• I've "fixed a bug"/"made an enhancement" in OpenSTA, what should I do?
• How can I help?

OpenSTAs relationship with the money driven world

• If OpenSTA is free how can I be charged money for it?
• Are there any parts of OpenSTA I have to pay for?
• I have commercial offerings related to OpenSTA, can I advertise here and in other OpenSTA resources?
• Are there any hard copy books related to OpenSTA?
• Where can I purchase an OpenSTA support contract?
• Where can I purchase OpenSTA training?
• Where can I find skilled OpenSTA consultants?
• Where can I find staff proficient in OpenSTA?
• Can I pay for an OpenSTA enhancement/fix?
• Can I donate money/time/resources/people/food/animals to help OpenSTA progress?

ToDo: more good questions always need adding