ldapsearch command Fails for both TLS and Clear Text Connections with start_tls Error

Issue

• Failing to connect with start_tls error:

  Encrypted:

  [root@host ~]$ ldapsearch -v -D "cn=admin,dc=example,dc=com" -W 'password' -Z -H ldaps://ldap-server -b "CN=Users,dc=example,dc=com" -s sub (cn=testuser)
  ldap_initialize( ldaps://ldap-server:636/??base )
  ldap_start_tls: Can't contact LDAP server (-1)
          additional info: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed (unable to get local issuer certificate)
  ldap_sasl_bind(SIMPLE): Can't contact LDAP server (-1)
  

  Plain text:

  [root@host ~]$ ldapsearch -v -D "cn=admin,dc=example,dc=com" -W 'password' -Z -H ldap://ldap-server -b "CN=Users,dc=example,dc=com" -s sub (cn=testuser)
  ldap_initialize( ldap://ldap-server:389/??base )
  ldap_start_tls: Connect error (-11)
          additional info: error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed (unable to get local issuer certificate)
  ldap_result: Can't contact LDAP server (-1)