Freeradius error: "Discarding conflicting packet"

[Alan DeKok]

jelle-e wrote:
> Everything seems to run smoothly but before every login attempt the logs say
> (something like):
> 
> "Error: Discarding conflicting packet from client NAS-NAME port 3072 - ID: 3
> due to recent request 28."

  That's pretty definitive.

> After that the user logs in correctly.
> 
> I have no idea where to start searching for the answer. Since this error
> appears to occur on every AP, I don't think they're all 'broken'.

  It's possible.  If they're all the same manufacturer and software
version, they could all have the same bug.

> Does anybody have an idea? Thanks in advance!

  Run "tcpdump" or "wireshark" to look at the packets.  Odds are the
AP's *are* sending conflicting packets.  Look for 2 packets from the
same client IP && port, with the same RADIUS code and ID, within a
second of each other.  If the packet contents are different, then the AP
is broken.

  i.e. You can believe that FreeRADIUS is broken, but *only* on your
system... and not on the other 10,000 systems with 100's of 1000's of
AP's.  Or, you can believe that your AP's are broken.

  Alan DeKok.