WiFi constantly changes association

[Alan Stern]

On Wed, Aug 28, 2024 at 10:00:22PM +0300, Jouni Malinen wrote:
> On Wed, Aug 28, 2024 at 02:02:32PM -0400, Alan Stern wrote:
> > Attached is a compressed file containing a 10-minute section of the 
> > journalctl output.  wpa_supplicant was running with -ddt and without -s, 
> > so this should contain all of its output.
> > 
> > Initially both wpa_supplicant and NetworkManager were turned off.  The 
> > log starts at the time when I turned on wpa_supplicant, and a few 
> > seconds later, turned on NetworkManager.  An INVALID_IE event occurred 
> > at timestamp 12:03:59.  The output is so voluminous it's hard to see 
> > what's really happening, however.
> 
> Thanks. This seems to make it clear that the AP has an issue in its FT
> implementation at least in the BSS that operates on the 6 GHz band.
> Based on the OUI, that AP is from HPE (Aruba?), so I guess I'll check
> with them whether this is a known issue.

Yes, I believe Harvard uses Aruba hardware for their access points.

> The log did not include any other attempt to use the FT protocol, so I
> could not check whether it could have worked on other bands. However, I
> do note that the RSNE from the 5 GHz band is indeed different and
> matches the value that the AP included on the 6 GHz band in the
> Reassociation Response frame, so this seems to point towards some
> implementation or configuration issues on the AP side and that could
> result in an issue that is specific to the 6 GHz band.
> 
> PS.
> 
> The reason for this particular sequence is in the STA first connecting
> on the 5 GHz band and wpa_supplicant being configured to use bgscan
> to find a better candidate. Background scan from that ends up finding a
> 6 GHz AP and that has better estimated throughput and wpa_supplicant
> decides to roam based on that. Since FT is enabled here, that roam tries
> to use FT from the 5 GHz AP to the 6 GHz one and that fails. This
> results in the 6 GHz AP getting temporarily disabled and a 5 GHz AP
> being selected as the next option. That succeeds with initial FT
> mobility domain association (i.e., not using FT protocol). However, now
> we get back to that same state where bgscan will find a better AP on 6
> GHz and that will result in the same failure..

Is there a way to tell wpa_supplicant to ignore APs on the 6-GHz band?

> As far as I can tell, the main issue here is in AP misbehavior. This
> could be worked around by disabling FT or bgscan. A potential
> wpa_supplicant change could be considered to disable FT protocol for
> that specific AP when this type of behavior is detected. I'll talk to
> Aruba first to see if I can get a better understanding on what is behind
> this AP behavior.

Thanks.  If you need more information, let me know.

Alan Stern