Alert Query Result Contains Extra, Incorrect Data


Trying to work out why I’m seeing this behavior - happening across multiple Grafana installs,v6.3.5.

Simple panel tracking WAN latency (single series) from an influx datasource. Panel renders data fine.
I’ve added an alert that should fire when the link is down (when latency reported as 0).

However, I’ve found that when running ‘Test Rule’ - even on a link where the time period of the query returns all 0s, the rule evaluates to false as there is an extra (incorrect) data point in the list:


This appears when the time period for the alert query is (A, 5m, now). Setting it to (A, 5m, now-1m) seems to avoid the issue.

Why is having a value of now() causing the response to include this value from ~5months in the future, well outside the time series requested in the result? Manually running the same query on the influx server just returned 0s - no random value from Feb included!

Anyone have any idea why this is happening.