Probably the data you are pushing is dropped ?
If you insert records with a precision in seconds for example : 1555496690,
the database will think the year is 1970 …
> precision ns
> insert precisiontest field="ns" 1555496690000000000
> insert precisiontest field="s" 1555496690
ERR: {"error":"partial write: points beyond retention policy dropped=1"}
> show retention policies
name duration shardGroupDuration replicaN default
---- -------- ------------------ -------- -------
autogen 720h0m0s 168h0m0s 1 true
> alter retention policy autogen on telegraf duration inf
> insert precisiontest field="s" 1555496690
> precision rfc3339
> select * from precisiontest
name: precisiontest
time field
---- -----
1970-01-01T00:00:01.55549669Z s
2019-04-17T10:24:50Z ns
>
You could use telegraf to ingest the data because in telegraf you can specify a precision …
It is also a good idea to temporarily enlarge the shard duration before ingesting your historical data
