so in my case remotley upgraded from 17.01 to 18.06-rc2 dynamic dns, and openvpn setting gone,
18.06-rc2 to 18.06.0 same,
so leets say in general i lost contact with router forever.
I have to ask someone to run teamviewer and set up all things again from lan side.
anyone wondered from devs it can be issue?
this problem persist from 2013 ->
someone made script which is working or not working, not commited into mainline.
Question is: when service relase for 18.06.x will be there, i will get flushed again packages?
and yes i have ticked , persist settings
Settings can be preserved in sysupgrade, but not the installed packages.
Compiling private builds with needed packages is the easy solution to have packages installed in the image and working right after the flashing.
(that script from mforkel would not help if you lose connectivity due to absent VPN packages etc., as it requires access to the router after flashing)
Another option I personally use when upgrading remote devices is using the ImageBuilder to pack a customized image with relevant packages and configuration already included.
This also has the positive side effect that a "reset to defaults" would restore to the own custom builtin configs