How to recognise encrypted private SSL key

Problem

How to recognise an encrypted private key.

Solution

You can recognise and see if a key is encrypted by looking at the first lines of your private SSL key file. Below is an example:

• Key is encrypted  

-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: DES-EDE3-CBC,123456ABCD719580

diYueU...
-----END RSA PRIVATE KEY-----

• Key is not encrypted 

-----BEGIN RSA PRIVATE KEY-----
MIIEogI...
-----END RSA PRIVATE KEY-----