In the Virtual Service modify screen (Virtual Services > View/Modify Services > Modify) there is a check box in the SSL Properties section called Verify Client using OCSP. When this is enabled, the LoadMaster verifies that the client certificate is valid.

Note: If Verify Client using OCSP is enabled and the OCSP server settings have not been configured in the OCSP Configuration screen, the client cannot be verified and the connection will fail. There will not be a warning or error message on the WUI which indicates this so please ensure to check this if troubleshooting any problems.