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MX Administrative Interface: Difference between revisions
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==== Log interval ====
This is time selected from a drop-down between times when MX logs current values
*A shorter time interval here has advantage of a greater chance of logging daily maximum and minimum values, but leads to bigger files. Because the log only records spot values (not as one enhancement requested maximum and minimum since last log) there remains a good chance of missing the extremes when logging.
*Conversely, choosing a longer time here increases chance of not recording extremes, but reduces the storage needs on the device running MX.
*For some weather station types, this interval
**Davis stations in particular can struggle to do a correct catch-up when MX is restarted if the intervals do not match, and that catch-up download can be of every log in the logger and take a long time.
**Calculations like average temperature and wind run are based on every measurement processed by MX. If you don't run MX all the time, it can only process what is in the station logger for the times when MX is not running. An average will be skewed if some of the inputs to that average are based on rapid sampling while MX is running and some on infrequent logs when it is not running.
**If the station logger interval and this log interval are set to same number, then entries in the log files will be at same interval when MX is running and when the Cumulus log entries are populated from station log entries. If they disagree, the Cumulus log will store lines at the station logging interval during catch-up on restart and at the interval set here when MX is running normally; you might not want your Cumulus logs to have such a mixture.
**If the station log interval is too short, the station logger might not hold enough entries if the Cumulus user is not able to keep MX running continuously or if MX fails for some reason. This tends to be the reason why some users want their station logger interval longer; they need to be able to retain say whatever length of time they might be on holiday. So some people will set that station interval to longer than this Cumulus interval (for normal running, they wish to maximise the values that are logged).
From version 3.7.0 if you use a Davis station, a warning will be output if the log interval set here does not match the Davis logger interval. The developer says:
▲For some weather station types, this interval must match the interval at which the logger associated with the station logs readings, for some types it does not matter, and some station types don't have a separate logger.
<pre>This is just a warning. Its best to keep the logger intervals the same to avoid excessively long start-ups, but it isn't mandatory.
I have put the warning in because lots of people aren't aware they have the issue.
Some people may choose to run with a MX interval of say 5 minutes and a station logger of 30 minutes because they say need to cope with extended offline periods. That is a conscious decision though, and they can ignore the warning.</pre>
==== Log rollover ====
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