Before finding this guide, I ran into the Port 80 problem described in this page (likely blocked by ISP) and [posted about it in the LetsEncrypt forums](https://community.letsencrypt.org/t/help-with-standalone-certbot-failed-to-bind-to-80-using-ipv4/37701/8). While this excellent guide helped me circumvent that immediate issue, a certbot engineer suggested an alternate method for automated cert renewal that did not require manually changing port mapping every time a cert needed to be renewed.
In short, he suggested using a TLS challenge rather than HTTP, so that the Let's Encrypt CA would bind port 443 externally, and specify certbot to bind to port 8123 internally for certificate renewal. He also added that pre- and post-hooks could be passed to certbot so that HA could be stopped/started and port 8123 could be freed for cert renewal.
I have verified that this method works in a dry run on my own HA setup and modified step 8 with some suggested documentation
* Added note about RPi's 100 mbit limit
In my case, I just realized after months that RPi hav 100 mbit card, so this was the limiting factor :)
* Update
* Optional variables added to sensor.cups.markdown
Sensor configuration supports two additional variables which are not listed but would be extremely helpful to anyone running their print server on a host other than the one running Home Assistant.
Added two lines to the Configuration variables section to show host and port optional values.
* Fix formatting
* Add periods
* Add instructions for setting using discovery with the Harmony hub
* Leave the default example to be manual configuration and separate advanced configuration into separate section.
* Add note that the config variable is optional
* Revert deletion of example comment
* Revert deletion of example comment
* Additional documentation
Added documentation for additional parameters introduced by a separate change request (already included in 0.48)
KNX should be moved from the "DIY" section as KNX isn't a DIY solution, but an industry standard used for building automatisation.
* Removed some example code
