A method to copy InfluxDB data in localhost to InfluxDB online every X seconds?

I have 2 influx databases: 1 on localhost, 1 online accessible from a domain. I save data to the local influx database every few seconds and I want to make a copy every few seconds to the online influx (acting as a cloud). Now, another feature would be great to have: if you lose connection to the cloud, some kind of local buffer collects the data and syncs with the online influx once the connection is up again.

Solution

I suggest to run only one version influxdb.

Telegraf data collector supports buffering of data in case of network issues.

metric_buffer_limit controls how many metrics are buffered.

Quoted from telegraf documentation.

  ## Maximum number of unwritten metrics per output.  Increasing this value
  ## allows for longer periods of output downtime without dropping metrics at the
  ## cost of higher maximum memory usage.
  metric_buffer_limit = 10000

Adjusting the buffer limit should help in saving the metrics without loss due to network glitches. There is no need to run two influxdb instances for this.