Recently I’ve been playing a bit with Grafana and InfluxDB data sources populated by collectd for the most part. However when trying to explore the data in InfluxDB, all times were in 1970-01-01. The epoch is often used as a kind of null value in InfluxDB. However in this case, the time value were increasing. The problem was that there was a mismatch between the timestamp sent by collectd and the way InfluxDB was trying to parse them.

Collectd used the write_influxdb_udp write plugin which apparently sends timestamp in milliseconds, but the [[udp]] listener of InfluxDB was probably expecting them to be in nanoseconds. Hence, there factor 1000000 between the two timestamp formats. You can control which format InfluxDB expects on its [[udp]] listener using the following parameter:

# InfluxDB precision for timestamps on received points ("" or "n", "u", "ms", "s", "m", "h")
precision = "ms"