Health Check monitor

All VLT/VLTI data are transferred over the internet to the Garching NGAS archive. From there they are retrieved by QC Garching. Calibration data usually have a very small delivery delay, often just a few minutes. QC Garching processes new calibration data in order to derive information about the health of the instruments. This is done in an automatic, incremental way: once per hour, 24 hours a day, 7 days a week. The quality information is derived in form of QC1 parameters. These parameters are trended and scored. Scoring is an evaluation against configured thresholds and provides a simple but sensitive feedback: green means all is OK, red means there might be a problem.

The Health Check monitor collects QC1 parameters and their scores. It does not aim at completeness but is focusing on the critical instrument components. The results are presented in two views: the graphical HEALTH CHECK monitor with the full trending reports, and the QUICK-LOOK monitor with scores. They are connected through the links HC plot... and scores&comments... .

The Health Check monitor is a component of the real-time QC system. Its other main components are the calChecker (calibration completeness), and the AB product monitors with the complete set of products, QC1 parameters and scores for a given date.

Process. The Health Check process is fed by calibrations that measure key instrument components ("health check calibrations"). They are taken regularly, in many cases daily. They are pipeline processed by QC Garching in an automatic process that is triggered every hour. The pipelines derive QC1 parameters which are stored in a database. Some more advanced QC1 parameters are derived by post-pipeline QC procedures and added to the database. The most recent QC1 values are trended, that means plotted together with a historical data set (often the last 90 days).

Scoring. The trending is supported by scoring, a process in which a new parameter is evaluated against configured thresholds. These thresholds can be fixed (e.g. specifications), or relative (like +/- 10% around the medain as calculated from the trending).

Opslog data. A second data set is included here, namely the QC1 parameters derived from the Paranal on-line pipelines. These data are collected in opslog files and transferred via ftp. They are included here as a fall-back solution in case of problems with the data transfer. They are derived with default processing parameters and a static calibration database. They are less accurate than the final QC1 parameters as calculated by the Garching pipelines, and therefore have no permanent value. Like the final QC1 parameters, opslog data are checked ("parsed") by QC Garching once per hour. Whenever a new entry is detected, the corresponding Health Check plot is updated.

The health of the opslog ftp process and of the parser process is monitored by a small java application:

	ftp
	parser

Check out here possible actions in case of alerts.

Trending plots. The Health Check monitor offers access to the following trending plots:

• Health Check plots: the ones compiling the QC1 values for the most important and regularly measured instrument components (marked by in the horizontal navigation bar) and including OPSLOG data,
• similar ones without OPSLOG data (marked no OPSLOG data) (because e.g. the pipeline does not produce them),
• plots with data which are only infrequently measured (driven by the calibration plan),
• the QUICK-LOOK reports with instrument scores (linked under scores&comments... )
• the complete available historical set (linked under history).

QC1 database. You can download the QC1 parameters, and also connect to the QC1 database.

Tutorial. Most plots have a corresponding tutorial page linked as tutorial. Some supporting information is available under This plot. The statistical result of each plot and each data set are listed in the result table.

The process behind the Health Check Monitor is documented in more detail here.