Fri Nov 06, 2015 2:55 pm
Thanks for the suggestions. I'll experiment with the read only root image and see if it can be bend to my will.
The reason I don't want to store data locally is because in some instances, I may have no control over the boot cycle (how much, how often) because the board may be regularly powered up and down. When the system is up, I simply either want it to forward data to a server, or hold the data until the server asks for it. The concept being that the Pi would monitor whatever it does constantly, but the server really only wants average snapshots and peak data. if the server stores data in an rrd every 5 minutes, it's no big deal to miss an occasional peak, but constantly missing them hurts. For instance, I want a Pi to manage and monitor solar data (battery voltage, bi-directional battery current, solar panel voltage, weather data, etc...) local data retrieved every 5 minuets via wireless network is fine. The Pi is overkill for that (especially with X on it), but at $35 who cares. By using the Pi, I can gain hardware standardization and the same Pi with a touch screen can also house an automation control point. Distributed computing at $35 a pop is a strong motivator for standardization. That is also why the package management is necessary. The hardware may be the same at every node (plus or minus sensors and display), the OS may be the same, but the package required for the job will be unique. it's an intriguing concept that a $35 price point makes possible. it also makes having spares on hand an easy task. Right now, I have to have a spare of at least 12 different embedded platforms.
Forwarding the data via network isn't an issue for me. I have my own WAN and the data never leaves my control. If I want more security to send it out into the cloud (for whatever reason, maybe I'm traveling and I want remote access) The Pi is powerful enough to run real time encryption. I'm liking this little board if I can get the base software to do what I want.
The controlling server would, of course, have more traditional storage like a hard drive, but with the distributed nature of the imagined system, the Pi might even be able to handle that.