How to set CApath for NGINX SSL Connection -

I am trying to set up an SSL connection from SagePay from my website. I can run openssl s_client successfully, it returns: Confirm return code: 0 (OK) , but only if I specify CApath example

  Openssl s_client -connect test .sagepay.com: 443 -Cache / USR / local / SSL / seriat /  

When I try to use the website I receive an error: < / P>

  OpenSSL :: SSL :: SSLError (SSL_connect = = errno = 0 state = read SSLv3 server certificate B: verify certificate is failed):  

How do I get SGL Siros? Have installed?