Could not add STA to kernel driver

Tue Aug 11 08:38:43 EDT 2020

Hi

Thanks for answer Markus.
Don't know why but I have found this message via mail list archive and 
couldn't find it in my mailbox, so I have copied content below from archive.

Anyway, my setup for 80 devices is very specific it is used to upload mp3 files 
content into devices with ESP32-WROOM processor which is only 2.4GHz capable.
Uploading will happen a few times in year, so it does not have to be extremely 
reliable all the time and I could also split devices by software and upload to 
40 devices and then next 40. However splitting it by 10 will make upload time 
very long.

Can you recommend good wifi card for this task? Or a chipset I should be 
looking for ? It would be good if it has strong antenna. Current system I'm 
using is Debian Buster with kernel v 4.19

Best,
Marek

> Hi,
> 
> On 8/5/20 11:08 AM, Marek.Floriańczyk wrote:
> > Hi
> > 
> > I have a question.  I have Debian Buster with hostapd 2.7 from packages. I
> > would like to run AP with 80 devices connected to it without any
> > encryption,
> > at the bottom there is my configuration file.
> 
> I don't know why this happens after 10 STAs for you, but iwlwifi/mvm
> supports
> at most 16 STAs, as far as I can see. So you better look after a card
> which can
> actually handle 80 devices.
> 
> Please note that having a NIC which can connect 80 devices and having a
> nicely working
> setup with 80 devices transmitting concurrently are two different things.
> If a large amount of your devices are transmitting concurrently, I'd
> advise you to use multiple
> APs tuned to different channels, each handling a much lower amount of
> clients. Maybe 20 - 30.
> If your setup works after using multiple APs also depends on the
> external interference in the environment.
> 
> Furthermore I would advise you to use 5 GHz channels if possible (I know
> Intel NICs don't support 5 GHz in AP
> mode).
> 
> Markus
> 
> > The problem is that after 11 devices has been connected, I can see in
> > hostapd
> > logs this message:
> > wlp3s0: STA 4c:11:ae:f9:a0:fc IEEE 802.11: authenticated
> > wlp3s0: STA 4c:11:ae:f9:a0:fc IEEE 802.11: associated (aid 11)
> > wlp3s0: AP-STA-CONNECTED 4c:11:ae:f9:a0:fc
> > wlp3s0: STA 4c:11:ae:f9:a0:fc RADIUS: starting accounting session
> > 7D19D5A198595E57
> > wlp3s0: STA 4c:11:ae:f9:7c:e4 IEEE 802.11: Could not add STA to kernel
> > driver
> > wlp3s0: STA 4c:11:ae:f8:ee:fc IEEE 802.11: Could not add STA to kernel
> > driver
> > 
> > I have kernel
> > vmlinuz-4.19.0-10-amd64
> > 
> > Debug from dmesg about wifi module:
> > [    7.276894] Intel(R) Wireless WiFi driver for Linux
> > [    7.317193] iwlwifi 0000:03:00.0: firmware: direct-loading firmware
> > iwlwifi-3168-29.ucode
> > [    7.318027] iwlwifi 0000:03:00.0: loaded firmware version
> > 29.1044073957.0
> > op_mode iwlmvm
> > [    7.516613] iwlwifi 0000:03:00.0: Detected Intel(R) Dual Band Wireless
> > AC
> > 3168, REV=0x220
> > [    7.548539] iwlwifi 0000:03:00.0: base HW address: d4:3b:04:51:69:e0
> > [    7.670030] iwlwifi 0000:03:00.0 wlp3s0: renamed from wlan0
> > 
> > My computer is Udoo x86 with this wifi module:
> > https://shop.udoo.org/kit-m2-wifi-bt.html
> > 
> > hostapd.conf
> > #
> > # nl80211 mode
> > #
> > 
> > ssid=fmcode
> > interface=wlp3s0
> > hw_mode=g
> > channel=5
> > #bridge=br0
> > driver=nl80211
> > 
> > logger_syslog=1
> > logger_syslog_level=1
> > wmm_enabled=0
> > wpa=0
> > preamble=0
> > 
> > #wpa_psk=
> > #wpa_passphrase=
> > #wpa_key_mgmt=WPA-PSK
> > 
> > #wpa_pairwise=TKIP
> > #rsn_pairwise=CCMP
> > #auth_algs=1
> > #macaddr_acl=0
> > 
> > #noscan=1
> > 
> > ### IEEE 802.11n
> > #ieee80211n=1
> > #ht_capab=
> > #country_code=US
> > #ieee80211d=1
> > ### IEEE 802.11n
> > 
> > ### IEEE 802.11a
> > #hw_mode=a
> > ### IEEE 802.11a
> > 
> > ### IEEE 802.11ac
> > #ieee80211ac=1
> > #vht_capab=[MAX-MPDU-11454][SHORT-GI-80][TX-STBC-2BY1][RX-STBC-1][MAX-A-MP
> > DU-
> > LEN-EXP3]
> > #vht_oper_chwidth=1
> > #vht_oper_centr_freq_seg0_idx=42
> > ### IEEE 802.11ac
> > 
> > # controlling enabled
> > ctrl_interface=/var/run/hostapd
> > ctrl_interface_group=0
> > 
> > #End
> > 
> > Any idea why only 10 devices can be connected. Actually I have the same
> > issue
> > on my laptop with different hardware.
> > 
> > Best Regards
> > Marek
> > 
> > 
> > 
> > 
> > 
> > _______________________________________________
> > Hostap mailing list
> > Hostap at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/hostap
> 
> --
> Markus Theil
> 
> Technische Universität Ilmenau, Fachgebiet Telematik/Rechnernetze
> Postfach 100565
> 98684 Ilmenau, Germany
> 
> Phone: +49 3677 69-4582
> Email: markus[dot]theil[at]tu-ilmenau[dot]de
> Web: http://www.tu-ilmenau.de/telematik
> --
> Marek Floriańczyk
> FMCode.pl
> 502-126-187 