[Tue Jun 23 02:05:52 2015] [error] Unable to configure RSA server private key
[Tue Jun 23 02:05:52 2015] [error] SSL Library Error: 185073780 error:0B080074:x509 certificate routines:X509_check_private_key:key values mismatch
The above is an accurate description of what is wrong.
In our case the client made a simple mistake of thinking the localhost.crt and localhost.key (default key locations for Apache SSL in Centos) were in the same directory but they were not. This meant that the .crt and .key did not match and this will never work for those who know how PKI (Public Key Infrastructure) works. It is like using the wrong key that does not match the door, it will never work.
So the solution is to Verify the stated paths and locations of the key and certificate (make sure it is what you expect and where the files really are.
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