When install Rocket chat so must be install ssl using free or purchase. Now I have to show you can using Let’Encrypt fully free ssl service. This certificate default valid date 3 month. But I setup auto renewal process on my server. If your server is local so must be using NAT system for forward port.

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NAT PORT 443 (LAN) ➺ 443 (WAN) << Parmenent
NAT PORT 80 (LAN) ➺ 80 (WAN)     << Only for before install ssl

My Public IP address : 45.251.231.171
My Local IP address : 10.66.30.10

Step #01: Must be your server update & upgrade then install nginx web server.

root@Rocket-Chat:~# apt-get update
root@Rocket-Chat:~# apt-get install software-properties-common python-software-properties
root@Rocket-Chat:~# apt-get install nginx
root@Rocket-Chat:~# systemctl status nginx.service

Before install ssl so must be disable 80 port from your server.

root@Rocket-Chat:~# netstat -pan | grep ":80"
root@Rocket-Chat:~# pkill -f nginx
root@Rocket-Chat:~# systemctl start nginx.service
root@Rocket-Chat:~# systemctl status nginx.service

Step #02: Now install let’sencrypt and certbot and configure nginx web server.

root@Rocket-Chat:~# add-apt-repository ppa:certbot/certbot
root@Rocket-Chat:~# apt-get update
root@Rocket-Chat:~# apt-get install letsencrypt
root@Rocket-Chat:~# wget https://dl.eff.org/certbot-auto -P /usr/local/bin
root@Rocket-Chat:~# chmod a+x /usr/local/bin/certbot-auto
root@Rocket-Chat:~# export DOMAIN="chat.technologyrss.com"
root@Rocket-Chat:~# export EMAIL_ALERT="admin@technologyrss.com"

Step #03: Install free SSL from let’sencrypt for nginx server.

root@Rocket-Chat:~# /usr/local/bin/certbot-auto certonly --standalone -d $DOMAIN  --preferred-challenges http --agree-tos -n -m  $EMAIL_ALERT --keep-until-expiring

Backup old nginx web config file and edit for using ssl.

root@Rocket-Chat:~# cp /etc/nginx/sites-available/default /etc/nginx/sites-available/default.back
root@Rocket-Chat:~# vi /etc/nginx/sites-available/default

Step #04: Drop previous all lines and insert below all lines. And change your domain name for ssl config.

# Upstream definition
upstream backend {
    server 127.0.0.1:3000;
}
# http to https redirection
server {
  listen 80;
  server_name chat.technologyrss.com;
  rewrite ^ https://$server_name$request_uri? permanent;
}
# HTTPS Server
server {
    listen 443;
    server_name chat.technologyrss.com;
    error_log /var/log/nginx/rocket-chat.access.log;
    ssl on;
    ssl_certificate /etc/letsencrypt/live/chat.technologyrss.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/chat.technologyrss.com/privkey.pem;
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2; # don’t use SSLv3 ref: POODLE
    location / {
        proxy_pass http://backend/;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $http_host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forward-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forward-Proto http;
        proxy_set_header X-Nginx-Proxy true;
        proxy_redirect off;
    }
}

Step #05: Restart nginx web server and run renew command.

root@Rocket-Chat:~# nginx -t
root@Rocket-Chat:~# service nginx restart
root@Rocket-Chat:~# certbot-auto renew

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