| Bridged Wireless Access Point |
| |
| For wireless adapters based on the following chipsets: |
| |
| rtl8811cu |
| rtl8821cu |
| |
| 2021-01-23 |
| |
| Tested setup: |
| |
| Raspberry Pi 4B (4gb) |
| Raspberry Pi OS (2021-01-11) (32 bit) |
| WiFi Adapter Driver: https://github.com/morrownr/8821cu.git |
| Onboard WiFi disabled |
| Ethernet connection providing internet |
| USB WiFi Adapter based on the rtl8811cu chipset |
| |
| Steps: |
| |
| 1. Install the driver for the WiFi adapter. |
| |
| Follow instructions at this site: |
| |
| https://github.com/morrownr/8821cu.git |
| |
| ----- |
| |
| 2. Disable Raspberry Pi onboard WiFi: |
| |
| $ sudo nano /boot/config.txt |
| |
| Add: |
| |
| dtoverlay=disable-wifi |
| |
| ----- |
| |
| 3. Change driver options: |
| |
| $ sudo nano /etc/modprobe.d/8821cu.conf |
| |
| rtw_vht_enable=2 (enable 80 Mhz channel width) |
| |
| ----- |
| |
| 4. Update system: |
| |
| $ sudo apt update |
| $ sudo apt full-upgrade |
| $ sudo reboot |
| |
| ----- |
| |
| 5. Install needed packages: |
| |
| $ sudo apt install hostapd |
| |
| ----- |
| |
| 6. Enable the wireless access point service and set it to start |
| when your Raspberry Pi boots: |
| |
| $ sudo systemctl unmask hostapd |
| $ sudo systemctl enable hostapd |
| |
| ----- |
| |
| 7. Add a bridge network device named br0 by creating a file using |
| the following command, with the contents below: |
| |
| $ sudo nano /etc/systemd/network/bridge-br0.netdev |
| |
| File contents: |
| |
| [NetDev] |
| Name=br0 |
| Kind=bridge |
| |
| ----- |
| |
| 8. Determine the names of the network interfaces: |
| |
| $ ip link show |
| |
| Note: If the interface names are not eth0 and wlan0, then the |
| interface names used in your system will have to replace eth0 |
| and wlan0 during the remainder of this document. |
| |
| ----- |
| |
| 9. Bridge the Ethernet network with the wireless network, first |
| add the built-in Ethernet interface ( eth0 ) as a bridge |
| member by creating the following file: |
| |
| $ sudo nano /etc/systemd/network/br0-member-eth0.network |
| |
| File contents: |
| |
| [Match] |
| Name=eth0 |
| |
| [Network] |
| Bridge=br0 |
| |
| ----- |
| |
| 10. Enable the systemd-networkd service to create and populate |
| the bridge when your Raspberry Pi boots: |
| |
| $ sudo systemctl enable systemd-networkd |
| |
| ----- |
| |
| 11. Block the eth0 and wlan0 interfaces from being |
| processed, and let dhcpcd configure only br0 via DHCP. |
| |
| $ sudo nano /etc/dhcpcd.conf |
| |
| Add the following line near the beginning of the file (above the |
| first interface xxx line, if any): |
| |
| denyinterfaces wlan0 eth0 |
| |
| Go to the end of the file and add the following: |
| |
| interface br0 |
| |
| ----- |
| |
| 12. To ensure WiFi radio is not blocked on your Raspberry Pi, |
| execute the following command: |
| |
| $ sudo rfkill unblock wlan |
| |
| ----- |
| |
| 13. Create the hostapd configuration file: |
| |
| $ sudo nano /etc/hostapd/hostapd.conf |
| |
| File contents: |
| |
| ## hostapd.conf |
| ## https://w1.fi/hostapd/ |
| ## rtl8811cu USB WiFi Adapter |
| ## 5g, 80211ac, channel width 80, 434 Mb/s |
| |
| interface=wlan0 |
| bridge=br0 |
| driver=nl80211 |
| ctrl_interface=/var/run/hostapd |
| ctrl_interface_group=0 |
| |
| ssid=pi |
| wpa_passphrase=raspberry |
| |
| country_code=US |
| ieee80211d=1 |
| ieee80211h=0 |
| |
| #2g |
| #hw_mode=g |
| #channel=7 |
| |
| #5g |
| hw_mode=a |
| channel=36 |
| #channel=149 |
| |
| macaddr_acl=0 |
| auth_algs=1 |
| ignore_broadcast_ssid=0 |
| wmm_enabled=1 |
| wpa=2 |
| wpa_key_mgmt=WPA-PSK |
| #wpa_pairwise=TKIP |
| rsn_pairwise=CCMP |
| |
| ##### IEEE 802.11n related configuration ##### |
| ieee80211n=1 |
| # 8811cu |
| ht_capab=[HT40+][SHORT-GI-20][SHORT-GI-40][MAX-AMSDU-7935] |
| |
| ##### IEEE 802.11ac related configuration ##### |
| ieee80211ac=1 |
| # 8811cu |
| vht_capab=[MAX-A-MPDU-LEN-EXP3][MAX-MPDU-11454][SHORT-GI-80] |
| vht_oper_chwidth=1 |
| vht_oper_centr_freq_seg0_idx=42 |
| #vht_oper_centr_freq_seg0_idx=155 |
| |
| # |
| ## end of hostapd.conf |
| |
| ----- |
| |
| 14. Establish conf file and log file locations: |
| |
| $ sudo nano /etc/default/hostapd |
| |
| Add to bottom of file: |
| |
| DAEMON_CONF="/etc/hostapd/hostapd.conf" |
| DAEMON_OPTS="-d -K -f /home/pi/hostapd.log" |
| |
| ----- |
| |
| 15. Reboot the system |
| |
| $ sudo reboot |
| |
| ----- |
| |
| 16. Enjoy! |
| |
| ----- |
| |
| iperf3 results: |
| |
| $ iperf3 -c 192.168.1.40 |
| Connecting to host 192.168.1.40, port 5201 |
| [ 5] local 192.168.1.9 port 37866 connected to 192.168.1.40 port 5201 |
| [ ID] Interval Transfer Bitrate Retr Cwnd |
| [ 5] 0.00-1.00 sec 31.7 MBytes 266 Mbits/sec 0 682 KBytes |
| [ 5] 1.00-2.00 sec 31.2 MBytes 262 Mbits/sec 0 814 KBytes |
| [ 5] 2.00-3.00 sec 27.5 MBytes 231 Mbits/sec 0 1012 KBytes |
| [ 5] 3.00-4.00 sec 30.0 MBytes 252 Mbits/sec 0 1.04 MBytes |
| [ 5] 4.00-5.00 sec 28.8 MBytes 241 Mbits/sec 0 1.10 MBytes |
| [ 5] 5.00-6.00 sec 30.0 MBytes 252 Mbits/sec 0 1.10 MBytes |
| [ 5] 6.00-7.00 sec 31.2 MBytes 262 Mbits/sec 0 1.24 MBytes |
| [ 5] 7.00-8.00 sec 30.0 MBytes 252 Mbits/sec 0 1.30 MBytes |
| [ 5] 8.00-9.00 sec 31.2 MBytes 262 Mbits/sec 0 1.30 MBytes |
| [ 5] 9.00-10.00 sec 31.2 MBytes 262 Mbits/sec 0 1.30 MBytes |
| - - - - - - - - - - - - - - - - - - - - - - - - - |
| [ ID] Interval Transfer Bitrate Retr |
| [ 5] 0.00-10.00 sec 303 MBytes 254 Mbits/sec 0 |
| [ 5] 0.00-10.01 sec 300 MBytes 251 Mbits/sec |
| |
| iperf Done. |
| |
| |
