Let's Encrypt with the Ubiquiti EdgeRouter

This guide uses https://letsencrypt.org/ and https://github.com/Neilpang/acme.sh to generate a valid SSL certificate for the EdgeRouter.

• Does not ever expose the admin GUI to the internet
• 100% /config driven, does not require modification to EdgeOS system files

Install/Update acme.sh & scripts

• Connect via ssh to your EdgeRouter and execute the following command.

curl https://raw.githubusercontent.com/j-c-m/ubnt-letsencrypt/master/install.sh | sudo bash

Configuration

• In the steps below replace/verify the following:
  • subdomain.example.com - FQDN
  • 192.168.1.1 - LAN IP of Router
• Configure DNS record for subdomain.example.com to your public WAN IP.
• Connect via ssh to your EdgeRouter.

1. Initialize your certificate.

   sudo /config/scripts/renew.acme.sh -d subdomain.example.com
   

   You can include additional common names for your certificate, so long as they resolve to the same WAN address:

   sudo /config/scripts/renew.acme.sh -d subdomain.example.com -d subdomain2.example.com
   

2. Enter configuration mode.

   configure
   

3. Setup static host mapping for FQDN to the LAN IP.

   set system static-host-mapping host-name subdomain.example.com inet 192.168.1.1
   

4. Configure cert-file location for gui.

   set service gui cert-file /config/ssl/server.pem
   set service gui ca-file /config/ssl/ca.pem
   

5. Configure task scheduler to renew certificate automatically.

   set system task-scheduler task renew.acme executable path /config/scripts/renew.acme.sh
   set system task-scheduler task renew.acme interval 1d
   set system task-scheduler task renew.acme executable arguments '-d subdomain.example.com'
   

   If you included multiple names in step 1, you'll need to include any additional names here as well.

   set system task-scheduler task renew.acme executable arguments '-d subdomain.example.com -d subdomain2.example.com'
   

6. Commit, save and exit configuration mode.

   commit
   save
   exit
   

7. Accesss your router by going to https://subdomain.example.com

Changelog

20231119 - Update install script to create ssl directory
20231112 - Install script now fetches updated cacert bundle for curl
20230208 - Update option handling to pass --staging and --test to acme.sh
           Update reload command to use vars, fixes ECDSA key issues
20220624 - Update acme.sh repo to https://github.com/acmesh-official/acme.sh
20210622 - Update option handling to pass --debug and --force to acme.sh
20210621 - Default to Let's Encrypt CA
         - Add -f to force renew
20200419 - Use SIGTERM for GUI service stop
20200109 - Use systemctl on 2.0 to start GUI service
20191022 - Prevent sudo error
20190311 - Initialize certificate first outside of configuration mode
20180609 - Install script
20180605 - IPv6 support
20180213 - Deprecate -i <wandev> option
20171126 - Add ca.pem for complete certificate chain
         - Temporarily disable http port forwarding during renew
20171013 - Remove reload.acme.sh
20170530 - Check wan ip
20170417 - Stop gui service during challenge
20170320 - Add multiple name support
20170317 - Change from standalone to webroot auth using lighttpd
20170224 - Bug fixes
20170110 - Born