Problem in ACS5.1 : "EAP session timed out", "RADIUS Request dropped "

Question

Hi .
Part of my access points do not want to authenticate wi-fi users (through Radius server and Microsoft AD) .
The scheme is: wi-fi PC-access point -ACS server 5.1 (Radius)-Microsoft AD
After I  configured some AP, next logs we can see :
EAP session timed out (many)
RADIUS Request dropped (many)
Could not establish connection with ACS Active Directory agent
User's Groups retrieval from Active Directory failed
The user is not found in the internal users identity store.
Another part of devices (AP) works well.
Anyone can help me to solve this problem please?

Answer 1

Hi Nicolas.
In logs usually we see some steps of beginning relations between devices. But here we see only one log line:
What can it mean?
The other messages seem to indicate that there is a problem with your AD. Did you test the bind ? Can you retrieve the AD groups list from ACS ?
Yes, we tested relations between AD and ACS, AD groups list retrieve fine from AD. In addition half of devices in network works fine: wi-fi devices authenticates excellent .
Do you use AD with the ACS for another part of your network that would be working fine ?
Yes, there is single AD and ACS.