Realtek Wifi is Not Working on Xubuntu 18.04 LTS with RTL8723BU

**boundule** · August 11th, 2018

I have just installed latest Xubuntu 18.04 LTS on my new purchased low config laptop along side Windows 10 (duel boot). Everything of Installation was working fine but the Wifi is not working. Sometimes (rarely) i was able to connect to my wifi router but the network strength is too much week. My laptop uses realtek driver (may be RTL8723BU) for wifi. It is working fine in Windows 10 system. From inxi -Fxz command I found that my Network card not installed somehow. In Xumuntu I am now totally without internet. Here I want to add that I have no Wired LAN option in this laptop.

How can I fix / solve this wifi / network card problem??

inxi -Fxz

Code:

System:    Host: BUDDY Kernel: 4.15.0-30-generic x86_64 bits: 64 gcc: 7.3.0 Desktop: Xfce 4.12.3 (Gtk 2.24.31)
           Distro: Ubuntu 18.04.1 LTS
Machine:   Device: laptop System: Walton product: Prelude R1 serial: N/A
           Mobo: N/A model: N/A serial: N/A
           UEFI: American Megatrends v: WH-BI-14-Y116AR120-105-C date: 03/13/2018
CPU:       Dual core Intel Celeron N3350 (-MCP-) arch: N/A cache: 1024 KB
           flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx) bmips: 4377
           clock speeds: max: 2400 MHz 1: 869 MHz 2: 861 MHz
Graphics:  Card: Intel Device 5a85 bus-ID: 00:02.0
           Display Server: x11 (X.Org 1.19.6 ) drivers: modesetting (unloaded: fbdev,vesa)
           Resolution: 1366x768@60.00hz
           OpenGL: renderer: Mesa DRI Intel HD Graphics 500 (Broxton 2x6)
           version: 4.5 Mesa 18.0.5 Direct Render: Yes
Audio:     Card Intel Celeron N3350/Pentium N4200/Atom E3900 Series Audio Cluster
           driver: snd_hda_intel bus-ID: 00:0e.0
           Sound: Advanced Linux Sound Architecture v: k4.15.0-30-generic
Network:   Card: Failed to Detect Network Card!
Drives:    HDD Total Size: 1008.2GB (1.2% used)
           ID-1: /dev/sda model: HGST_HTS541010B7 size: 1000.2GB
           ID-2: USB /dev/sdb model: Transcend_8GB size: 8.0GB
Partition: ID-1: / size: 19G used: 4.6G (27%) fs: ext4 dev: /dev/sda7
           ID-2: /home size: 35G used: 51M (1%) fs: ext4 dev: /dev/sda9
           ID-3: swap-1 size: 6.14GB used: 0.00GB (0%) fs: swap dev: /dev/sda8
RAID:      No RAID devices: /proc/mdstat, md_mod kernel module present
Sensors:   System Temperatures: cpu: 49.0C mobo: N/A
           Fan Speeds (in rpm): cpu: N/A
Info:      Processes: 166 Uptime: 37 min Memory: 397.8/3778.5MB Init: systemd runlevel: 5 Gcc sys: 7.3.0
           Client: Shell (bash 4.4.191) inxi: 2.3.56

lspci; lsusb

Code:

00:00.0 Host bridge: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series Host Bridge (rev 0b)
00:00.1 Signal processing controller: Intel Corporation Device 5a8c (rev 0b)
00:02.0 VGA compatible controller: Intel Corporation Device 5a85 (rev 0b)
00:0e.0 Audio device: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series Audio Cluster (rev 0b)
00:0f.0 Communication controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series Trusted Execution Engine (rev 0b)
00:12.0 SATA controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series SATA AHCI Controller (rev 0b)
00:15.0 USB controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series USB xHCI (rev 0b)
00:16.0 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #1 (rev 0b)
00:16.1 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #2 (rev 0b)
00:16.2 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #3 (rev 0b)
00:16.3 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #4 (rev 0b)
00:17.0 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #5 (rev 0b)
00:17.1 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #6 (rev 0b)
00:17.2 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #7 (rev 0b)
00:17.3 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series I2C Controller #8 (rev 0b)
00:18.0 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series HSUART Controller #1 (rev 0b)
00:18.1 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series HSUART Controller #2 (rev 0b)
00:18.2 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series HSUART Controller #3 (rev 0b)
00:18.3 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series HSUART Controller #4 (rev 0b)
00:19.0 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series SPI Controller #1 (rev 0b)
00:19.1 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series SPI Controller #2 (rev 0b)
00:19.2 Signal processing controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series SPI Controller #3 (rev 0b)
00:1c.0 SD Host controller: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series eMMC Controller (rev 0b)
00:1f.0 ISA bridge: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series Low Pin Count Interface (rev 0b)
00:1f.1 SMBus: Intel Corporation Celeron N3350/Pentium N4200/Atom E3900 Series SMBus Controller (rev 0b)
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 058f:5608 Alcor Micro Corp. 
Bus 001 Device 004: ID 0bda:b720 Realtek Semiconductor Corp. 
Bus 001 Device 003: ID 09da:c10a A4Tech Co., Ltd. 
Bus 001 Device 002: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
Bus 001 Device 006: ID 058f:6387 Alcor Micro Corp. Flash Drive
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

usb-devices | awk '/b720/' RS=

Code:

T:  Bus=01 Lev=01 Prnt=01 Port=06 Cnt=04 Dev#=  4 Spd=480 MxCh= 0
D:  Ver= 2.10 Cls=ef(misc ) Sub=02 Prot=01 MxPS=64 #Cfgs=  1
P:  Vendor=0bda ProdID=b720 Rev=02.00
S:  Manufacturer=Realtek
S:  Product=802.11n WLAN Adapter
S:  SerialNumber=00e04c000001
C:  #Ifs= 3 Cfg#= 1 Atr=e0 MxPwr=500mA
I:  If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
I:  If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
I:  If#= 2 Alt= 0 #EPs= 6 Cls=ff(vend.) Sub=ff Prot=ff Driver=rtl8xxxu

**kc1di** · August 11th, 2018

Is it possible to connect that machine via Ethernet cable?

**praseodym** · August 11th, 2018

If LAN works, try

Code:

sudo apt-get install git build-essential
git clone https://github.com/lwfinger/rtl8723bu
cd rtl8723bu
make
sudo make install
sudo modprobe -v 8723bu
iwconfig

**jeremy31** · August 11th, 2018

Download https://www.dropbox.com/s/pog7bujlma...8723bu.ko?dl=0 in windows and copy the file to Ubuntu desktop, then in terminal

Code:

sudo cp 8723bu.ko /lib/modules/$(uname -r)/kernel/drivers/net/wireless/
sudo depmod -a

Reboot and wifi should work, then do

Code:

sudo apt install git build-essential dkms
git clone https://github.com/lwfinger/rtl8723bu.git
sudo dkms add rtl8723bu

Then it should build when new kernels are installed

**boundule** · August 11th, 2018

the out put..

########## wireless info START ##########

Report from: 11 Aug 2018 19:37 +06 +0600

Booted last: 11 Aug 2018 00:00 +06 +0600

Script from: 10 Jan 2018 20:04 UTC +0000

##### release ###########################

Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic

##### kernel ############################

Linux 4.15.0-30-generic #32-Ubuntu SMP Thu Jul 26 17:42:43 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

Parameters: ro, quiet, splash, vt.handoff=1

##### desktop ###########################

Xubuntu

##### lspci #############################

##### lsusb #############################

Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 005: ID 058f:5608 Alcor Micro Corp.
Bus 001 Device 004: ID 0bda:b720 Realtek Semiconductor Corp.
Bus 001 Device 003: ID 09da:c10a A4Tech Co., Ltd.
Bus 001 Device 002: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
Bus 001 Device 007: ID 058f:6387 Alcor Micro Corp. Flash Drive
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

##### PCMCIA card info ##################

##### rfkill ############################

0: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no

##### lsmod #############################

rtl8xxxu 122880 0
mac80211 778240 1 rtl8xxxu
cfg80211 622592 2 8723bu,mac80211

##### interfaces ########################

[/etc/network/interfaces]
auto lo
iface lo inet loopback

##### ifconfig ##########################

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 6482 bytes 390514 (390.5 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 6482 bytes 390514 (390.5 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

wlx88835db994da: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.43.207 netmask 255.255.255.0 broadcast 192.168.43.255
inet6 fe80::bf36:f88b:db7e:26c5 prefixlen 64 scopeid 0x20<link>
ether 88:83:5d:b9:94:da txqueuelen 1000 (Ethernet)
RX packets 76 bytes 37970 (37.9 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 113 bytes 20222 (20.2 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

##### iwconfig ##########################

lo no wireless extensions.

wlx88835db994da IEEE 802.11 ESSID:"buddy7"
Mode:Managed Frequency:2.437 GHz Access Point: 3E:97:0F:B5:03:E0
Bit Rate=1 Mb/s Tx-Power=20 dBm
Retry short limit:7 RTS thr=2347 B Fragment thr

ff
Power Management

ff
Link Quality=38/70 Signal level=-72 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:32 Missed beacon:0

##### route #############################

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.43.1 0.0.0.0 UG 600 0 0 wlx88835db994da
169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 wlx88835db994da
192.168.43.0 0.0.0.0 255.255.255.0 U 600 0 0 wlx88835db994da

##### resolv.conf #######################

nameserver 127.0.0.53

##### network managers ##################

Installed:

NetworkManager

Running:

root 577 1 0 18:56 ? 00:00:00 /usr/sbin/NetworkManager --no-daemon

##### NetworkManager info ###############

GENERAL.DEVICE: wlx88835db994da
GENERAL.TYPE: wifi
GENERAL.NM-TYPE: NMDeviceWifi
GENERAL.VENDOR: Realtek
GENERAL.PRODUCT: 802.11n WLAN Adapter
GENERAL.DRIVER: rtl8xxxu
GENERAL.DRIVER-VERSION: 4.15.0-30-generic
GENERAL.FIRMWARE-VERSION: N/A
GENERAL.HWADDR: 88:83:5D:B9:94

A
GENERAL.MTU: 1500
GENERAL.STATE: 100 (connected)
GENERAL.REASON: 0 (No reason given)
GENERAL.UDI: /sys/devices/pci0000:00/0000:00:15.0/usb1/1-7/1-7:1.2/net/wlx88835db994da
GENERAL.IP-IFACE: wlx88835db994da
GENERAL.IS-SOFTWARE: no
GENERAL.NM-MANAGED: yes
GENERAL.AUTOCONNECT: yes
GENERAL.FIRMWARE-MISSING: no
GENERAL.NM-PLUGIN-MISSING: no
GENERAL.PHYS-PORT-ID: --
GENERAL.CONNECTION: buddy7
GENERAL.CON-UUID: e5fe578a-d3aa-4f7c-ab00-a0a747b5d870
GENERAL.CON-PATH: /org/freedesktop/NetworkManager/ActiveConnection/1
GENERAL.METERED: yes (guessed)
CAPABILITIES.CARRIER-DETECT: no
CAPABILITIES.SPEED: 1 Mb/s
CAPABILITIES.IS-SOFTWARE: no
CAPABILITIES.SRIOV: no
WIFI-PROPERTIES.WEP: yes
WIFI-PROPERTIES.WPA: yes
WIFI-PROPERTIES.WPA2: yes
WIFI-PROPERTIES.TKIP: yes
WIFI-PROPERTIES.CCMP: yes
WIFI-PROPERTIES.AP: no
WIFI-PROPERTIES.ADHOC: no
WIFI-PROPERTIES.2GHZ: yes
WIFI-PROPERTIES.5GHZ: no
IP4.ADDRESS[1]: 192.168.43.207/24
IP4.GATEWAY: 192.168.43.1
IP4.ROUTE[1]: dst = 0.0.0.0/0, nh = 192.168.43.1, mt = 600
IP4.ROUTE[2]: dst = 192.168.43.0/24, nh = 0.0.0.0, mt = 600
IP4.ROUTE[3]: dst = 169.254.0.0/16, nh = 0.0.0.0, mt = 1000
IP4.DNS[1]: 192.168.43.1
DHCP4.OPTION[1]: requested_subnet_mask = 1
DHCP4.OPTION[2]: requested_rfc3442_classless_static_routes = 1
DHCP4.OPTION[3]: subnet_mask = 255.255.255.0
DHCP4.OPTION[4]: domain_name_servers = 192.168.43.1
DHCP4.OPTION[5]: ip_address = 192.168.43.207
DHCP4.OPTION[6]: requested_static_routes = 1
DHCP4.OPTION[7]: dhcp_server_identifier = 192.168.43.1
DHCP4.OPTION[8]: requested_time_offset = 1
DHCP4.OPTION[9]: broadcast_address = 192.168.43.255
DHCP4.OPTION[10]: dhcp_rebinding_time = 3150
DHCP4.OPTION[11]: requested_interface_mtu = 1
DHCP4.OPTION[12]: requested_domain_name_servers = 1
DHCP4.OPTION[13]: dhcp_message_type = 5
DHCP4.OPTION[14]: requested_broadcast_address = 1
DHCP4.OPTION[15]: routers = 192.168.43.1
DHCP4.OPTION[16]: dhcp_renewal_time = 1800
DHCP4.OPTION[17]: requested_domain_name = 1
DHCP4.OPTION[18]: requested_routers = 1
DHCP4.OPTION[19]: expiry = 1533998195
DHCP4.OPTION[20]: host_name = BUDDY
DHCP4.OPTION[21]: requested_netbios_scope = 1
DHCP4.OPTION[22]: requested_wpad = 1
DHCP4.OPTION[23]: requested_ms_classless_static_routes = 1
DHCP4.OPTION[24]: requested_netbios_name_servers = 1
DHCP4.OPTION[25]: network_number = 192.168.43.0
DHCP4.OPTION[26]: requested_domain_search = 1
DHCP4.OPTION[27]: requested_ntp_servers = 1
DHCP4.OPTION[28]: next_server = 192.168.43.1
DHCP4.OPTION[29]: vendor_encapsulated_options = ANDROID_METERED
DHCP4.OPTION[30]: dhcp_lease_time = 3600
DHCP4.OPTION[31]: requested_host_name = 1
IP6.ADDRESS[1]: fe80::bf36:f88b:db7e:26c5/64
IP6.GATEWAY: --
IP6.ROUTE[1]: dst = ff00::/8, nh = ::, mt = 256, table=255
IP6.ROUTE[2]: dst = fe80::/64, nh = ::, mt = 256
IP6.ROUTE[3]: dst = fe80::/64, nh = ::, mt = 600
CONNECTIONS.AVAILABLE-CONNECTION-PATHS: /org/freedesktop/NetworkManager/Settings/{3}
CONNECTIONS.AVAILABLE-CONNECTIONS[1]: e5fe578a-d3aa-4f7c-ab00-a0a747b5d870 | buddy7

SSID BSSID MODE CHAN FREQ RATE SIGNAL BARS SECURITY ACTIVE IN-USE
buddy7 3E:97:0F:B5:03:E0 Infra 6 2437 MHz 65 Mbit/s 48 ▂▄__ WPA2 yes *

##### NetworkManager.state ##############

[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true

##### NetworkManager.conf ###############

[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=false

[device]
wifi.scan-rand-mac-address=no

##### NetworkManager profiles ###########

**boundule** · August 16th, 2018

Originally Posted by jeremy31

Download https://www.dropbox.com/s/pog7bujlma...8723bu.ko?dl=0 in windows and copy the file to Ubuntu desktop, then in terminal

Code:

sudo cp 8723bu.ko /lib/modules/$(uname -r)/kernel/drivers/net/wireless/
sudo depmod -a

Reboot and wifi should work, then do

Code:

sudo apt install git build-essential dkms
git clone https://github.com/lwfinger/rtl8723bu.git
sudo dkms add rtl8723bu

Then it should build when new kernels are installed

The wifi signal is so weak. sometimes not connected. if router is only 1 m distance then it work only

**boundule** · September 4th, 2018

My problem was solved by Following way:

1st Step:

Code:

sudo apt install build-essential dkms
sudo apt install git
git clone https://github.com/lwfinger/rtl8723bu.git
sudo apt install libelf-dev

2nd Step:

Code:

sudo -i
echo blacklist rtl8xxxu >> /etc/modprobe.d/blacklist.conf
exit

This ensured that the old driver was not be used for my device. In my case the problematic driver was rtl8xxxu. So I black listed it.

3rd Step: Now I disabled a line in the makefile of the new driver, because without this hack, two instances of the wireless chipset was shown in Network Manager

Code:

cd rtl8723bu
nano Makefile

Go down to line 21 and change this line:

Code:

EXTRA_CFLAGS += -DCONFIG_CONCURRENT_MODE

To comment it out, like this:

Code:

#EXTRA_CFLAGS += -DCONFIG_CONCURRENT_MODE

Save (Ctrl+o followed by Enter) and exit (Ctrl+x) the text editor.

4th Step: Now build and install the driver:

Code:

source dkms.conf
sudo mkdir /usr/src/$PACKAGE_NAME-$PACKAGE_VERSION
sudo cp -r core hal include os_dep platform dkms.conf Makefile rtl8723b_fw.bin /usr/src/$PACKAGE_NAME-$PACKAGE_VERSION
sudo dkms add $PACKAGE_NAME/$PACKAGE_VERSION
sudo dkms autoinstall $PACKAGE_NAME/$PACKAGE_VERSION

5th Step: Finally, install the compiled module with this command:

Code:

make
sudo make install

Reboot your computer.

**ludwig00** · September 21st, 2018

Hi, I have the same problem. I try to use your method, but I'm blocked at "source dkms.conf". Bash can't find it...

**jeremy31** · September 21st, 2018

Try

Code:

cd ~
sudo dkms add rtl8723bu
sudo dkms install rtl8723bu/4.3.6.11_12942.20141204_BTCOEX20140507-4E40
cd rtl8723bu
sudo cp rtl8723*.bin /lib/firmware/rtlwifi/

Reboot