I want to replace the telnet logging approach and have the following requirements:
1. Logging does work even if the esp is not connected to the internet
2. When the esp connects to the internet it appends it's local log file (that includes messages from 1.) to a remote server
Background:
It is important to keep message that were produced in 1.) because my esp for a temperature logging temporarily doesn't send the latest measurements to a remote server. It should do every 10 minutes. Most of the time it connects after 2-3h hours but then I do not know what happened in the meantime and don't know the reason for this passout without logs.
Does anybody know a library to archive this? How do you do logging?