How to use Let's encrypt Certificate for Firewall HTTPS page

Do you have the correct DNS Record on this IP / XG Interface? 

Do you have a Port 80 NAT Policy to this Linux server? 

https://community.sophos.com/kb/en-us/122976

DNS is correct but no DNAT policy for port 80 to the above linux server!

Hi,

you will need this rule because the certbot will host a website on Port 80 and lets encrypt will try to access this website via port 80 to verify the domain.

Cheers

After creating the rule for certbot, Now I have successfully secured my Sophos Appliance page with let's encrypt SSL.

As the certificate is valid for 90 days, if I forgot to renew it shall it effect the opening of the appliance page?

Renewal process has to be done manually it seems.

True, you have to do the process again after 90 days. Would recommend to schedule a reminder (as i do so). 

Tbh, the process will take 10 mins, overall 40 minute in 1 year. Would be possible to script something (cronjob with XML API script to enable the DNAT rule and XML API push to replace the cert). 

Maybe i will do this one time... 

You will get a normal "invalid / expired" certificate alert after 90 days.