AFAIK, custom SSL for both HA and mosquitto are possible. You have to place the certificate files in share folder for example and then indicate that path in config file and in the mosquitto addon options.
SSL was pretty painless… There is already an empty folder called /ssl where I put the key and certificate. in the configuration.yaml, I had to specify “/ssl/keyfile.key” and “/ssl/certificate.crt” whereas in the mosquito add-in config (through the hass.io tab), I had to ommit the “/ssl” part.
Now I need to figure out if I can run command line python scripts that access a serial port and also if I can define dev rules. Job for tonight.
I know this is kind of an old thread but did you ever manage to talk to devices via your serial port using Hass.io.
It looks to me like Hass.io doesn’t support running python scripts from a command line in Hass.io. I haven’t found any way to use the RS-232 port of the raspberry pi when using Hass.io as the operating system. Thanks.