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The Rules are processed when a device's details are processed - during discovery and/or upon processing an audit result (hence, they usually run multiple times). Rules conform to the usual priority system - they will override every thing that's not a user input via the GUI. Rules are considered to be YOUR rules. Not something derived from a device. Hence they mean more than (say) something retrieved via SSH or SNMP or WMI. This is because if they don't do what you want YOU CAN CHANGE THEM.
NOTE - At present we cannot delete a rule input or output that contains a /. This is because the framework is parsing the / as part of the URL and returning a 404, even before our code runs. The work-around for this is to delete the Rule itslef, then recreate the inputs and outputs as required. Fortunately inputs and outputs that contain a / are rare (indeed, none exist by default).
Rules have two main sections - inputs and outputs.
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So, that was a ride... In testing our new Rules feature worked a treat. In practice, not so much. Most servers (ie, not mine) can't cope with loading the rule set, even if we break it down to smaller chunks, when processing multiple devices. What to do? What to do? Well we've taken a small step back. Rules still exist as a feature, and they still work a treat. But instead of inserting 100,000 Rules into the database, we've split them up into four distinct files and implemented them as code only. Hence, no loading all 100,000 Rules, decoding JSON and running them against a device. Now we just load the files and run the statements. Much, much faster and more memory efficient. No load on MySQL, and hence the CPU also drops. No populating a massive recordset and hence the memory drops. The not so good thing - these are no longer editable in the GUI. But it's not the end of the world. You can still make Rules as you see fit and they will be run after the "default" rules (those in code), hence you can override the "default" rules. So we don't lose much, but we gain a LOT of performance. We also added a few new Rules for Mac Models.
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