I am experiencing an issue where I know the correct data is making it to Graphite (Postgresql), but when pulled into Grafana a single series on two panels reports NULL values.
How do I troubleshoot this? Where do I look for answers?
Initially, when I first created the panels, all series reported properly using the LAST aggregation, then suddenly started showing INVALID NUMBER. I changed the aggregation to AVG, and this fixed the problem temporarily. Now, nothing I use works.
Looking at the database used by Graphite, I see the correct data (numbers) in the tables, but for some reason pulling that into Grafana is showing NULL values.
Again, I have no idea where to look other than the database, and the numbers are correct in the database. Query viewer shows NULL values for everything in these two series.
NOTE: Another panel that gets its data from the same place works without issue.