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Ken
Asked: 2018-08-26 04:19:04 +0800 CST

Wi-Fi doesn't work on Ubuntu 18.04.1 LTS (RTL8723BE)

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When I installed Ubuntu for the first time I had to do some work with the terminal because my Wi-Fi reception was lower than on Windows: 

echo "options rtl8723be ips=0 fwlps=0 ant_sel=1" | sudo tee /etc/modprobe.d/rtl8723be.conf

After updating Ubuntu to bionic beaver my Wi-Fi randomly stops and my browser says that I am not connected to internet. I need to turn off and on my Wi-Fi to use the network. I searched on internet and I followed instructions in this answer. Now my pc says "no Wi-Fi adapter found"

I tried doing:

sudo apt-get install --reinstall bcmwl-kernel-source

with a reboot. And I have also tried:

sudo apt remove bcmwl-kernel-source && sudo apt install git dkms
git clone -b extended https://github.com/lwfinger/rtlwifi_new.git
sudo dkms add ./rtlwifi_new
sudo dkms install rtlwifi-new/0.6

but nothing.

lshw -C network says that my wireless net adapter is unclaimed:

  *-network UNCLAIMED       
   description: Network controller
   product: RTL8723BE PCIe Wireless Network Adapter
   vendor: Realtek Semiconductor Co., Ltd.
   physical id: 0
   bus info: pci@0000:02:00.0
   version: 00
   width: 64 bits
   clock: 33MHz
   capabilities: pm msi pciexpress cap_list
   configuration: latency=0
   resources: ioport:2000(size=256) memory:91200000-91203fff

What can I do? I am fairly new with Ubuntu.

Edit:

I have tried this answer, but it says "Unable to locate package rtlwifi-new-dkms"

networking wireless drivers 18.04 rtl8723be

2 Answers

  1. Best Answer

    What kernel version are you running?

    You can type uname -r in a terminal to get it

    I spent long hours to figure out that the problem had something to do with the 4.15.0-33-generic kernel. I switched to the previous one (-32) and everything worked again.

    However, i just managed to install the "rtlwifi_new" you mentioned, and now wifi seems to be fine even on latest one.

    So, on the 33 kernel, I plugged in the eth cable and executed the following commands:

    • sudo apt-get install build-essential git
    • git clone https://github.com/lwfinger/rtlwifi_new/
    • cd rtlwifi_new
    • make
    • sudo make install

    And in rc.local script I've put these two commands:

    • sudo modprobe -r rtl8723be
    • sudo modprobe rtl8723be ant_sel=1

    Then I rebooted the system

    Hope this can help

    • 4

  2. That unload/reload of rtl8723be may not work. Under some circumstances, the chip remembers the ant_sel option and ignores the one set on antenna reload. The safer way is to create an options file in /etc/modprobe.d/ that sets the ant_sel option.

    Also be aware that there have been changes in the btcoex code that changed the best value from 1 to 2.

    • 1