Backup parts of database from not running instance

I just messed around with my system and had my test system collecting data for about one day. Unfortunately, the test system stopped working and I had to switch back to my original system. But now the question is, how to get the influxdb-data from the test system into the database of my original system?

I know about influxd backup, which also supports to limit the time frame. This would actually be what I am looking for. But since I cannot get my test system running, I cannot use this command to backup the data.

However, I have access to the drive of the test system. So I could just copy the files of /var/lib/influxdb/. But this would contain the full time frame and not just the missing one day of data.

The only thing I can come up with is:

  1. Backup influxdb directory on original system
  2. Copy influxdb directory from test system to original system
  3. Run influxd backup ... to create the backup of the missing data
  4. Copy backup of original system’s influxdb directory back on the original system
  5. Include the backup created in step 3

Of course stopping and starting of the influx service as needed in between.

Is there a better way to achieve the desired result?

By the way: I am using influxdb 1.8.3

Best regards