wpa_supplicant : Despite BSSID being fixed, BSS Transition Management Request triggers scanning

[Olivier Robert]

Dear list readers,

When connected to an ESS that has 2.4 GHz and 5 GHz BSSIDs, *but* with the client being locked to only one (the bssid network variable is set to an explicit value), upon receiving a transition management request from the AP + preferred list + disassociation imminent (the AP doesn’t disassociate in the end), wpa_supplicant proceeds to a full scan.

<3>WNM: Disassociation Imminent - Disassociation Timer 60
<3>WNM: Preferred List Available
<3>CTRL-EVENT-SCAN-STARTED
<3>CTRL-EVENT-SCAN-RESULTS

This of course is for nothing since the BSSID is fixed, and is especially not desirable in an environment where signal quality isn’t optimal. I understand that “Disassociation imminent” is a strong hint to go associate somewhere else, but the configuration is still clear, the bssid variable being set, the client is going to stay for better and worse.

Hence my questions :
- is this intended behaviour in this use case (i.e. may it change) ?
- are there any workarounds that I’m not aware of (such as e.g. setting the supplicant to ignore transition management requests) ? (I’m currently mitigating this by setting scan_cur_freq and passive_scan)

I use wpa_supplicant v2.10 (on Ubuntu 23.10).

With kind regards,

-- 
Olivier