Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Number of wireless clients in AP mode is very limited #3010

Open
martignoni opened this issue Jun 11, 2019 · 1 comment

Comments

Projects
None yet
2 participants
@martignoni
Copy link

commented Jun 11, 2019

I'm reporting this on Jamesh's advice (see this forum discussion).

Describe the bug
On RPi 3B+, on can expect an optimistic max. of 20-30 devices connected simultaneously via Wi-Fi.

To reproduce
Use case: the RPi serves as a wifi AP and a web server, that's all. No user is logged in the RPi in production use.

Nginx and php-fpm are optimized so that memory is not a problem. Flooding the web server using ApacheBench shows that memory is not a problem: available memory remains at around 600M at any time, even with 100 concurrent http requests! Swap is never used.

The limitation experienced is uniquely caused by concurrent wifi connections to the AP (hostapd). For that reason, I'm suspecting it's a wifi driver issue.

Expected behaviour
More client devices than a mere 20 can be simultaneously connected to the RPi in AP mode.

Actual behaviour
When about 20 devices are connected to the RPi in AP mode, the RPi freezes.

System

  • Model: Pi3B+
  • OS and version: Raspberry Pi reference 2019-04-08
  • Firmware: version 2e98b31d18547962e564bdf88e57b3df7085c29b (clean) (release) (start_cd)
  • Kernel: Linux moodlebox 4.19.42-v7+ #1219 SMP Tue May 14 21:20:58 BST 2019 armv7l GNU/Linux

Logs
Not applicable.

Additional context
This is the content of my /etc/hostapd/hostapd.conf:

# Set country code
country_code=US
# Name of the Wi-Fi interface
interface=wlan0
# Use the nl80211 driver
driver=nl80211
# Wi-Fi network name (SSID)
ssid2=4d6f6f646c65426f78
utf8_ssid=1
# Show or hide SSID
ignore_broadcast_ssid=0
# Use the 2.4GHz band
hw_mode=g
# The Wi-Fi channel
channel=11
# Enable 802.11n
ieee80211n=1
# Enable WMM
wmm_enabled=1
# Enable 40 MHz channels with short guard interval for 20 Mhz
#ht_capab=[MAX-AMSDU-3839][HT40+][SHORT-GI-20][SHORT-GI-40][DSSS_CCK-40]
ht_capab=[HT40][SHORT-GI-20][DSSS_CCK-40]
# Accept all MAC addresses
macaddr_acl=0
# Use WPA authentication
auth_algs=1
# Use WPA2
wpa=2
# Use a pre-shared key
wpa_key_mgmt=WPA-PSK
# The network passphrase
wpa_passphrase=moodlebox
# Use AES, instead of TKIP
rsn_pairwise=CCMP
# Enable hostapd_cli
ctrl_interface=/var/run/hostapd
ctrl_interface_group=0

@martignoni martignoni changed the title Wireless clients in AP mode is very limited Number of wireless clients in AP mode is very limited Jun 11, 2019

@Choupinounours

This comment has been minimized.

Copy link

commented Jul 5, 2019

Mhhh I meet the same problem ! Could be really useful to fix it !

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.