Following environment variables are set into sites volume as `common_site_config.json`. It means once the file is created in volume, the variables won't have any effect, you need to edit the common_site_config.json to update the configuration
-`DB_HOST`: MariaDB host, domain name or ip address.
-`DB_PORT`: MariaDB port.
-`REDIS_CACHE`: Redis cache host, domain name or ip address.
-`REDIS_QUEUE`: Redis queue host, domain name or ip address.
-`REDIS_SOCKETIO`: Redis queue host, domain name or ip address.
-`SOCKETIO_PORT: `: Port on which the SocketIO should start.
-`UPSTREAM_REAL_IP_ADDRESS `: The trusted address (or ip range) of upstream proxy servers. If set, this will tell nginx to trust the X-Forwarded-For header from these proxy servers in determining the real IP address of connecting clients. Default: 127.0.0.1
-`UPSTREAM_REAL_IP_RECURSIVE`: When set to `on`, this will tell nginx to not just look to the last upstream proxy server in determining the real IP address. Default: off
-`UPSTREAM_REAL_IP_HEADER`: Set this to the header name sent by your upstream proxy server to indicate the real IP of connecting clients. Default: X-Forwarded-For
-`SKIP_NGINX_TEMPLATE_GENERATION`: When set to `1`, this will not generate a default NGINX configuration. The config file must be mounted inside the container (`/etc/nginx/conf.d`) by the user in this case. Default: `0`
This container takes configuration from `common_site_config.json` which is already created by erpnext gunicorn container. It doesn't use any environment variables.