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This is run twice nightly by the trscrontab on pinger@pinger.slac.stanford.edu to ping the target www.slac.stanford.edu. Reflector.cgi has to run on www-wanmon since that is where the PlanetLab cookie is kept. Since one cannot remotely run a trscronjob on www-wan mon, there is a script (reflector.pl) to execute reflector.cgi via twice via a wget command. The first time it uses all enabled landmarks (the default). The second time it uses the disabled landmarks. Running it regularly ensures the tulip log files are current and therefore the analysis is also current.
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Using the results from the Tulip log analysis script we can identify the hosts and their success percentages. We opted to disable all the hosts which were having success less than 20%, and to enable the ones with success rate greater than 20%. The above mentioned script is in /afs/slac.stanford.edu/package/pinger/tulip and it performs the listed functions. It uses the LWP package to access the webpage, downloads the analyzed tulip log file, by requesting it from reflector using http://www-wanmon.slac.stanford.edu/cgi-wrap/reflector.cgi?function=analyze&days=days and saves it in a file and then parses the output to get: for option ability=1, the faulty (landmarks (i.e. the ones below 20% success rate by default) updating the database to disable such hosts; or option ability=0 the landmarks with a success rate greater than 20% and re-enables them in the database. It (tulip-tuning.pl) is run twice nightly (see the trscrontab) once to disable non working landmarks, once to enable landmarks that are now working again. The runs are before the sites.xml or sites-disabled.xml are created and specify using the tulip log file analyzed for the last 3 days.
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