OpenSSL Generating a Certificate Signing Request

Generate the Certificate Signing Request (CSR)

Apache with mod_ssl Enabled (No subjectAltName)

1. If required follow the OpenSSL Generating a Private Key procedure.
2. For Apache purposes, use the key with no pass phrase to generate the CSR file.
3. Generate the CSR from the private key using openssl.
   1. # openssl req -new -key <key_name>.key -out <csr_name>.csr
4. Enter the information as required by the prompts.
5. Verify the checksum of the key matches the checksum CSR.
   1. # openssl req -noout -modulus -in <csr_name>.csr | openssl md5

Apache with mod_ssl Enabled (With subjectAltName)

1. If required follow the OpenSSL Generating a Private Key procedure.
2. For Apache purposes, use the key with no pass phrase to generate the CSR file.
3. Create a config file to be configured with the multiple subdomains.

   cat << EOL >> <config_file>.cnf

4. Generate the CSR from the private key using openssl.

   # openssl req -new -key <key_name>.key -out <csr_name>.csr

5. Enter the information as required by the prompts.
6. Verify the checksum of the key matches the checksum CSR.

   # openssl req -noout -modulus -in <csr_name>.csr | openssl md5

Further Reading

1. How to Generate SSL key, CSR, and Self Signed Certificate for Apache