Networked Datalogger (Server)

Good afternoon,

I have a feasibility question, I have some CO2 sensors I am looking at which are able to report their value to a custom URL or the cloud through a WIFI network. I am wanting to measure the CO2 spatially throughout an area but won't always have internet access so I am looking towards Arduino to act as a datalogger.

The idea was, just to keep cost down to have an Aduino connected to an ethernet shield and from there that connects into a cheap (e.g. $20) router / wireless AP.

The Arduino would then act as a 'web server' so each device would request a URL or post to a URL with the sensor ID, and the CO2 value, the Arduino would receive this and then record the value to an SD card file that reflects that specific sensor serial/ID.

The sensors would all be turned on by person, so I am guessing that it would not be all sensors requesting the URL at once, but it is possible.

If the Arduino was not requesting to write to the same SD card file, would the above be feasable, or would simple HTTP GET / POST calls to the Arduino in addition to writing to SD cards likely be to much?

The sensor intervals would be say every 30 seconds to every minute.

Many thanks!