Creating a Self-Signed SSL Certificate

A self-signed SSL Certificate can be used if you want to make a secure connection to a server by encrypting the data like the HTTPS connection. We can utilize OpenSSL to generate the key and certificate. We can run $ sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /path/to/yourkey.key -out /path/to/yourcert.crt to generate the key and certificate files.

Some important parameters are as follows:

req: This specifies a subcommand for X.509 certificate signing request (CSR) management. X.509 is a public key infrastructure standard that SSL adheres to for its key and certificate management. Since we are wanting to create a new X.509 certificate, this is what we want.

-x509: This option specifies that we want to make a self-signed certificate file instead of generating a certificate request.

-nodes: This option tells OpenSSL that we do not wish to secure our key file with a passphrase. Having a password-protected key file would get in the way of Apache starting automatically as we would have to enter the password every time the service restarts.

-days 365: This specifies that the certificate we are creating will be valid for one year.

-newkey rsa:2048: This option will create the certificate request and a new private key at the same time. This is necessary since we didn't create a private key in advance. The rsa:2048 tells OpenSSL to generate an RSA key that is 2048 bits long.

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