Openssl trust chain validation problem

Issue

• The verification of a certificate chain failed when the following command is used:

  $ openssl s_client -showcerts -CAfile /etc/pki/root.crt -connect server.example.com:443
  CONNECTED(00000003)
  depth=1 C = COM, O = Foo, OU = Bar, CN = Internal Server CA
  verify error:num=20:unable to get local issuer certificate
  verify return:0