Ubiquiti removed keytool (and java) from recent releases of Unifi OS. This moves from keytool to openssl's native pkcs12.
Tested on Unifi Dream Machine which runs Unifi OS and a built-in Unifi controller.
Also added backup of existing files prior to change in case anything goes wrong, and update system configuration with compatible ciphers.
Default of a zone might be high, which is annoying when testing
with the ACME staging API. I think setting the TTL to 0 makes sense
as acme.sh is the only one checking this, so having an always up
to date response seems desirable.
3VAbdAVE