someone could tell me, what mean this?

[Mike Vzz]

 Wed Jun 18 15:39:22 2014 AP 'AP-56 ', MAC: 28:34:a2:b1:86:e0 disassociated previously due to Link Failure. Uptime: 0 days, 09 h 40 m 34 s . Reason: Capwap WTP Event reques

[Leo Laohoo]

Means your AP has lost network connectivity.  Could mean the following: 

1.  AP lost power; 

2.  Layer 1 issue to the AP; 

3.  Routing issue.

[Saurav Lodh]

One had similar issues , refer here

https://supportforums.cisco.com/discussion/11943656/capwap-messages-wism2-75102

[Vinod Arya]

You may also want to look into your network if there is any firewall in between and it is blocking the CAPWAP ports and traffic.

-Thanks

Vinod

[Abha Jha]

AP getting disconnecting due to link failure..

Please check for the firewall in between..