Tutorial from: https://www.storyblok.com/tp/automatic-ssl-multi-tenant
First we choose a EC2 instance with Amazon Linux and create it with the default settings.
Copy the IPv4 Public IP from the EC2 instance dashboard and connect to your instance using your private key.
ssh -i your_key.pem ec2-user@YOUR_EC2_IP
We will need to install OpenResty on the remote instance. What is OpenResty®? OpenResty® is a full-fledged web platform that integrates the standard Nginx core, LuaJIT and many carefully written Lua libraries. Lua gives OpenResty/nginx the power to make automatic SSL possible.
sudo yum-config-manager --add-repo https://openresty.org/package/amazon/openresty.repo
sudo yum install openresty
sudo yum install openresty-resty
On newer Amazon machines I got following error installing OpenResty:
https://openresty.org/package/amazon/2/x86_64/repodata/repomd.xml: \[Errno 14\] HTTPS Error 404 - Not Found
To fix that error you need to edit the repo file with sudo vim /etc/yum.repos.d/openresty.repo and exchange the $releasever placeholder of the baseurl to “latest” baseurl=https://openresty.org/package/amazon/latest/$basearch.
LuaRocks is the package manager we need to install the lua-resty-auto-ssl package.
wget http://luarocks.org/releases/luarocks-2.0.13.tar.gz
tar -xzvf luarocks-2.0.13.tar.gz
cd luarocks-2.0.13/
./configure --prefix=/usr/local/openresty/luajit \
--with-lua=/usr/local/openresty/luajit/ \
--lua-suffix=jit \
--with-lua-include=/usr/local/openresty/luajit/include/luajit-2.1
make
sudo make install
https://github.com/GUI/lua-resty-auto-ssl requires ggc for the installation process so we install it with yum.
sudo yum install gcc
As lua-resty-auto-ssl needs to write to the directory /etc/resty-auto-ssl we’ll add the user group www to our ec2-user.
sudo groupadd www
sudo usermod -a -G www ec2-user
Using the package manger luarocks we install lua-resty-auto-ssl and create the directory where the library will write it’s files to.
sudo /usr/local/openresty/luajit/bin/luarocks install lua-resty-auto-ssl
sudo mkdir /etc/resty-auto-ssl
sudo chown -R root:www /etc/resty-auto-ssl/
sudo chmod -R 775 /etc/resty-auto-ssl
We will need a self signed fallback certificate as a fallback to be able to start nginx.
sudo openssl req -new -newkey rsa:2048 -days 3650 -nodes -x509 \
-subj '/CN=sni-support-required-for-valid-ssl' \
-keyout /etc/ssl/resty-auto-ssl-fallback.key \
-out /etc/ssl/resty-auto-ssl-fallback.crt
After backing up our original nginx.conf we open vim to insert the required configuration for the server.
sudo mv /usr/local/openresty/nginx/conf/nginx.conf /usr/local/openresty/nginx/conf/nginx.backup.conf
sudo vim /usr/local/openresty/nginx/conf/nginx.conf
Insert following content to the nginx.conf (/usr/local/openresty/nginx/conf/nginx.conf)
user ec2-user www;
events {
worker_connections 1024;
}
http {
lua_shared_dict auto_ssl 1m;
lua_shared_dict auto_ssl_settings 64k;
resolver 8.8.8.8 ipv6=off;
init_by_lua_block {
auto_ssl = (require "resty.auto-ssl").new()
auto_ssl:set("allow_domain", function(domain)
return true
end)
auto_ssl:init()
}
init_worker_by_lua_block {
auto_ssl:init_worker()
}
server {
listen 443 ssl;
ssl_certificate_by_lua_block {
auto_ssl:ssl_certificate()
}
ssl_certificate /etc/ssl/resty-auto-ssl-fallback.crt;
ssl_certificate_key /etc/ssl/resty-auto-ssl-fallback.key;
}
server {
listen 80;
location /.well-known/acme-challenge/ {
content_by_lua_block {
auto_ssl:challenge_server()
}
}
}
server {
listen 127.0.0.1:8999;
client_body_buffer_size 128k;
client_max_body_size 128k;
location / {
content_by_lua_block {
auto_ssl:hook_server()
}
}
}
}
As the final step we start OpenResty as a system service.
sudo service openresty start
To test it out point your domain or subdomain to the IP address of your EC2 instance and open the browser with **https://**subdomain.yourdomain.com.
If you get an error or a invalid certificate checkout what’s happening tailing the nginx error.log. I had some directory rights issues and found it out by watching the error.log while reloading the website with https.
tail -F /usr/local/openresty/nginx/logs/error.log
To enable log rotation for Resty we also need to add a logrotate configuration like following:
$ sudo vim /etc/logrotate.d/resty
/etc/logrotate.d/resty
/usr/local/openresty/nginx/logs/*.log {
compress
copytruncate
create 0644 root root
delaycompress
missingok
rotate 7
sharedscripts
postrotate
kill -USR1 `cat /usr/local/openresty/nginx/logs/nginx.pid`
endscript
}
Then create the logrotation cronjob
$ sudo crontab -e
0 21 * * * /usr/sbin/logrotate -v /etc/logrotate.d/resty
Resource - Link
lua-resty-auto-ssl https://github.com/GUI/lua-resty-auto-ssl
OpenResty http://openresty.org
Let's Encrypt https://letsencrypt.org