Install Comodo SSL

install-comodo-ssl.md

Generate private key and csr file

openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr

server.key: it is the private key used on the TLS protocol.
server.csr: it is the required certificate signing request.

If all three certificates are listed separately, use the command:

cat your_domain.crt intermediate.crt root.crt >> ssl-bundle.crt

If the intermediate certificates are in one bundle, run:

cat your_domain.crt your_domain.ca-bundle >> ssl-bundle.crt

Make sure you save the ssl-bundle.crt file in the etc/ssl directory.

For Comodo SSL

cat SectigoRSAOrganizationValidationSecureServerCA.crt USERTrustRSAAAACA.crt AAACertificateServices.crt > your_domain.ca-bundle

To Update new SSL certificate in AWS Certificate Manager

Certificate body: STAR_your_domain.crt
Certificate private key: server.key
Certificate chain: your_domain.ca-bundle

nginx.conf

server {
  listen 443;
  ssl on;
  ssl_certificate /etc/ssl/ssl-bundle.crt;
  ssl_certificate_key /path/to/your_private.key;
  root /path/to/webroot;
  server_name your_domain.com;
  access_log /var/log/nginx/nginx.vhost.access.log;
  error_log /var/log/nginx/nginx.vhost.error.log;
  location / {
    root /var/www/;
    root  /home/www/public_html/your.domain.com/public/;
    index index.html;
  }
}