Problems installing SSL certificate on nginx with intermediate key

Question

I am trying to install an SSL certificate on my Ubuntu server. I have purchased the certificate from my CA and have downloaded the certificate itself and an intermediate certificate. As so:

my certificate: mydomain.crt
intermediate certificate: GandiStandardSSLCA.pem

I also have (made using openssl)

my private key (?): mydomain.key
and signing request: mydomain.csr

I have uploaded all these files to my server and followed a guide to combine my certificate with the intermediate:

cat mydomain.crt GandiStandardSSLCA.pem > mydomain-bundle.crt 

I then add the following to my vhost's config:

listen 443 ssl; ssl_certificate /etc/nginx/ssl/mydomain-bundle.crt; ssl_certificate_key /etc/nginx/ssl/mydomain.key; 

But when I go to restart nginx I get this error:

* Restarting nginx
* Stopping nginx nginx [ OK ]
nginx: [emerg] SSL_CTX_use_PrivateKey_file("/etc/nginx/ssl/mydomain.key") failed (SSL: error:0B080074:x509 certificate routines:X509_check_private_key:key values mismatch) nginx: configuration file /etc/nginx/nginx.conf test failed

Any ideas why and how to solve?

Answer 1

Does your key list ok:

openssl rsa -in /etc/nginx/ssl/mydomain.key 

Do the modulus of the key and the cert match:

openssl x509 -in mydomain.crt -modulus openssl rsa -in qa.server.key -modulus 

These numbers must match.