See 2.6 release notes at

• http://docs.mongodb.org/master/tutorial/configure-ssl/
• http://docs.mongodb.org/master/tutorial/upgrade-cluster-to-ssl/
• http://docs.mongodb.org/master/tutorial/configure-x509/

There are several places where we use sslOnly. The new valid options for the *sslMode options are now:

• disabled
• allowSSL
• preferSSL
• requireSSL

*See SERVER-11375

In addition, I believe the valid X.509 options are:

• keyFile
• sendKeyFile
• sendX509
• x509

Please note the capitalizations; e.g. here we present sendKeyfile.