- Added check to not attempt auto update if time sync is needed and not yet successful (delays 30 second to recheck).
- Added resync of time when DHCP or link state changes if online
- Added conditional* fallback from configured* NTP servers to the IP-named NTP servers, and then to the DNS named ones if that fails
- Added conditional* fallback from the configured* HTTP servers to the default DNS named ones.
- Uses the configuration* option for how many queries to run in parallel
- Added known static IPs for time servers (in case DNS resolution isn't up yet)
- Added time.cloudflare.com to fall-back NTP servers
- Added fallback to NTP via hostnames
- Logs the resultant time (and mode)
* Ensure the mDNS mode is set every time network state changes
Eliminates (mostly) duplicate code
* Add custom NTP and HTTP time sync servers
Since the ordering may have been previously defaulted and saved as "ntp,http", but that was being ignored and fallback-defaults were being used, in Ordering, `ntp` means use the fallback NTP servers, and `http` means use the fallback HTTP URLs. Thus `ntp_user_provided` and `http_user_provided` are the user specified static lists.
* Add support for using DHCP-provided NTP server
Marc Brooks
Daniel Collins
Aveline