MGMT (TX callback) fail - AP rt2x00 with Managed broadcom

Jouni Malinen j
Fri Aug 8 10:10:55 PDT 2008

On Fri, Aug 08, 2008 at 06:55:46PM +0200, Petr Novak wrote:

> I only guess, that therefore (unknown vendor) ACK fail:
> MGMT (TX callback) ACK
> unknown vendor specific information element ignored (vendor OUI 00:10:18 len=9)

This has nothing to do with whether the other end ACKs the Probe
Response. The vendor IE is just data inside the frame, ACK is low-level
acknowledgment of the frame itself (regardless of body contents).

> I thought, that ACK fail is not good = no connection between AP and client. Channels are set to auto (if I am right, it is not possible set exact number of AP channel in /etc/hostapd/hostapd.conf).

Well, I would not be that concerned with Probe Response ACKs assuming
you can get to authentication/association steps. If the client does not
even try to authenticate, it may not receive Beacon frames or Probe
Responses properly. Have you tried using a wireless sniffer to capture
what frames the AP is transmitting?

> I try to discover, why ACK fails everytime and AP with client is not connected.

Well, one of the TX callbacks reported success (the one shown above)..
Though, this may be from the broadcast deauth frame which would not need
an acknowledgment in the first place. Anyway, this looks like something
that requires debugging the driver, not hostapd.

Jouni Malinen                                            PGP id EFC895FA

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