Variant A.1: Use standard Unix tools
First, we have been looking at the obvious, basic variant based on
arecord and optionally
flac, as can already be seen at GitHub - opensourcebeehives/DataLogger: Long term audio and video datalogger or others. We know others running such a setup and have heard about mixed results.
The software is very basic, can be adapted to own needs and the whole system can be brought into the field very quickly.
For making such a thing multi-channel and platform-grade, we would need to wrap the mechanics of the Bash program AVrecord.sh interacting with
arecord into a more solid process manager. This would certainly be doable. Additionally, we would improve the program a bit on the upload side by using
rsync or similar tools. Easy.
But then, how to control this thing when rolled out onto 20 machines or so? SSHing into each machine? Further, how do we monitor internals of the system regarding detected hardware, loss of connectivity or other parameters? After operating this for a while, one might think about sending control commands to reduce the recording time and just send chunks of data to the downstream data collector.