Today i noticed a different behavior from NetXms, not sure from what version it started.
Basicly i have template for each logical drive letter: C,D,E etc. In that template, 2 dci is created per drive and one dci is with threshold value "%{dci-DiskFreeGB-C:50}". "dci-DiskFreeGB-C" is inherited from template and by default is empty. So expected behavior was when drive free space is under 50, trigger alert. But today i noticed that when empty "dci-DiskFreeGB-C" is inherited no alerts are triggered. When i set "dci-DiskFreeGB-C" manualy to 50 then it will work. So easy fix right, lets set template inherited value to 50, but for some reason it wount be inherited. Even if i remove node from template and do another config discovery, still no luck. Next i tryed to removed template custom atribute and re add note, from some mysterios place it still auto inherits it.
Any ideas ?
The thing is, that empty custom attribute is converted into integer and turns into 0.
Not sure when there were changes in this. But current behavior is actually correct one - if custom attribute exists, but is empty, we treat it as existing and do not apply the default value for threshold. For numeric threshold empty value is converted into 0.
Out of curiosity, if node inherites custom attribute + value from template and later that value is modified on node, will it return to template value at some point ?
Only if you'll remove overridden value from node.