这个和软件版本有关，
Q. What are the requirements for Access Points to join a Virtual Controller?
A.
• The Access Points must be upgraded to 7.3 software, before joining a virtual controller.
• Access points ordered starting Sept/2012, will ship with 7.3 software from manufacturing.
Q. Why do I need to get Access Points upgraded to 7.3 to join a virtual controller?
A.
• Virtual Controller uses Self Signed Certificates (SSC) as against the Manufacturing Installed Certificates (MIC) in the traditional controller.
• Access Point will be able to validate the SSC certificate provided by the virtual controller before joining.
Q. When will manufacturing start shipping Access Points with 7.3 software?
A. Access points ordered starting Sept/2012 will ship with 7.3 software.
Q. How do I upgrade Access Points shipped prior to Sept/2012 to 7.3 software?
A. If the access points are associated with a controller, use the current upgrade process using Cisco Prime or Controller to upgrade the Access Points to 7.3 software.
