On Thu, 2018-08-30 at 13:06 +0800, Dave Young wrote: > On 08/30/18 at 07:15am, Luca Coelho wrote: > > On Wed, 2018-08-29 at 14:54 +0800, Dave Young wrote: > > > [ 74.123114] wlp61s0: authenticate with 00:1f:c6:82:0a:57 > > > [ 74.126099] wlp61s0: send auth to 00:1f:c6:82:0a:57 (try 1/3) > > > [ 74.139740] wlp61s0: authenticated > > > [ 74.140142] iwlwifi 0000:3d:00.0 wlp61s0: disabling HE/HT/VHT due to WEP/TKIP use > > > [ 74.140146] iwlwifi 0000:3d:00.0 wlp61s0: disabling HT as WMM/QoS is not supported by the AP > > > [ 74.140149] iwlwifi 0000:3d:00.0 wlp61s0: disabling VHT as WMM/QoS is not supported by the AP > > > > Your AP seems to be configured to use WEP or TKIP, which is not allowed > > by IEEE802.11n, so we disable all the higher rates, as you can see > > here. It should still work, but you will only get very basic rates > > (i.e. slow). > > Luka, thanks for the suggestion, moved AP to use WPA2-personal + AES. > seems I got only two features disabled this time: > [ 20.949347] iwlwifi 0000:3d:00.0 wlp61s0: disabling HT as WMM/QoS is not supported by the AP > [ 20.949351] iwlwifi 0000:3d:00.0 wlp61s0: disabling VHT as WMM/QoS is not supported by the AP > [ 20.949622] wlp61s0: associate with 00:1f:c6:82:0a:57 (try 1/3) There are many interoperability problems with old 11n APs that either support a draft version of the specs or simply have bugs in their implementations of the 11n specs. When we detect these problems, we disable 11n rates, so connectivity will be slower, but it will at least remain connected. This seems to be the case with your AP. :( > > > [ 2521.068469] wlp61s0: deauthenticating from 00:1f:c6:82:0a:57 by local choice (Reason: 3=DEAUTH_LEAVING) > > > > Other than that I can't really see what is going on, except that > > something is deciding to disconnect here... > > > > So, first thing I'd suggest would be to try to reconfigure your AP to > > use something else than WEP or TKIP, just to see if it improves in any > > way. > > Will observe if it works or not. BTW, my old laptop Thinkpad T440s works > well with the same AP. I hope it improves. If not, we should debug it further. It's a good thing not to use WEP and TKIP anyway, because they're not very secure anyway. > > And BTW, is this a regression in recent kernels or has this always > > happened to you with this laptop/AP combination? > > From my observation it just always happen, but hmm not 100% sure.. Okay, so we don't have enough information on this. It doesn't matter. What is the NIC on your old T440s? -- Cheers, Luca.