Let's say something like this is being returned when attempting to start a Tomcat application server. To resolve this, check out my article Tomcat Encrypt inbound requests (SSL / TLS / keystore).

SSLHostConfig attribute certificateFile must be defined when using an SSL connector

You'll want to update the Tomcat SSL connector to look something like this, so that the connector is using keystoreFile.

<Connector 
  port="8443" 
  protocol="HTTP/1.1" 
  SSLEnabled="true" 
  maxThreads="150" 
  scheme="https" 
  secure="true"
  clientAuth="false"
  sslProtocol="TLS" 
  keystoreFile="ssl/my_keystore.p12" 
  keystorePass="itsasecret" 
  keyAlias="tomcat.example.com" 
/>