Setting up a SSL Cert from Comodo

I use Namecheap.com as a registrar, and they resale SSL Certs from a number of other companies, including Comodo.

These are the steps I went through to set up an SSL cert.

Purchase the cert

Prior to purchasing a cert, you need to generate a private key, and a CSR file (Certificate Signing Request). You'll be asked for the content of the CSR file when ordering the certificate.

openssl req -new -newkey rsa:2048 -nodes -keyout example_com.key -out example_com.csr
This gives you two files:

example_com.key -- your Private key. You'll need this later to configure ngxinx.
example_com.csr -- Your CSR file.
Now, purchase the certificate [1], follow the steps on their site, and you should soon get an email with your PositiveSSL Certificate. It contains a zip file with the following:

Root CA Certificate - AddTrustExternalCARoot.crt
Intermediate CA Certificate - COMODORSAAddTrustCA.crt
Intermediate CA Certificate - COMODORSADomainValidationSecureServerCA.crt
Your PositiveSSL Certificate - www_example_com.crt (or the subdomain you gave them)


steps
1. cat www_example_com.crt COMODORSADomainValidationSecureServerCA.crt  COMODORSAAddTrustCA.crt AddTrustExternalCARoot.crt > ssl-bundle.crt
2. mkdir -p /etc/nginx/ssl/example_com/
mv ssl-bundle.crt /etc/nginx/ssl/example_com
3.mv example_com.key /etc/nginx/ssl/example_com/
4.server {
    listen 443;

    ssl on;
    ssl_certificate /etc/nginx/ssl/example_com/ssl-bundle.crt;
    ssl_certificate_key /etc/nginx/ssl/example_com/example_com.key;

    # side note: only use TLS since SSLv2 and SSLv3 have had recent vulnerabilities
    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;

    # ...

}