Weak Wifi Signal - No Connection (HP Laptop / Realtek RTL8723be Adapter / LM 19)

[confuzzled]

Good evening,

I'm new to Linux, and as the title says, I'm having Wifi connection issues with my HP laptop, with a newly installed Linux Mint 19 (Cinnamon - 64 bit / Kernel: 4.15.0-42 / Dual boot with Win10). The laptop detects my wireless network (47-50% signal strength, at most) but has yet to successfully connect to it. The wireless adapter is a Realtek RTL8723be.

Before I get into the weeds of what I've already attempted to try and fix the problem, I ran JeremyB's wireless script:

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wget -N -t 5 -T 10 https://github.com/UbuntuForums/wireless-info/raw/master/wireless-info && chmod +x wireless-info && ./wireless-info

Here's the output:

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REMOVED

Note: SecureBoot is disabled.


I've tried the following:

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sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=1
iwlist scan | egrep -i 'ssid|quality'  >> Signal: 34%

sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=2
iwlist scan | egrep -i 'ssid|quality'  >> Signal: 37%

echo "options rtl8723be ant_sel=X" | sudo tee -a /etc/modprobe.d/rtl8723be.conf

Tried with X=1 & X=2; rebooted after each time. No change, no connection either way.

I then tried to install the rtlwifi_new drivers (even though I read -- afterwards -- that they weren't needed for the latest Linux kernels):

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sudo apt-get install dkms git build-essential
git clone -b extended https://github.com/lwfinger/rtlwifi_new.git
sudo dkms add ./rtlwifi_new
cd rtlwifi_new
make
sudo make install

Installation was successful (git status: On branch extended. Your branch is up to date with 'origin/extended'. Nothing to commit, working tree clean.) So I ran the previous antenna commands again (i.e. sudo modprobe...), rebooting each time to try antennas 1 & 2 successively. Result: no joy.


I reset the antenna to default (i.e. 0) and tried the following from a thread in this forum:

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echo "options rtl8723be fwlps=N ips=N" | sudo tee -a /etc/modprobe.d/rtl8723be.conf

Still no connection.


At this point, I'm stumped. If you've read to this point, thank you and I'm hoping you might have some helpful pointers/suggestions.

[JeremyB]

Is the wireless script result from before using the rtlwifi_new from github?

[confuzzled]

Is the wireless script result from before using the rtlwifi_new from github?

Thank you for looking at my problem. To answer your question: no, I ran the script after I ran out of things to try, meaning after I used the rtlwifi_new from github. I can run it again if that would be helpful.

Another data point that might or might not be relevant is that the Realtek adapter generated errors non-stop during boot, so I had to add the "pci=noaer" to the grub parameters to mask them (after researching the issue). The specific errors were as follows:

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PCIe Bus Error:severity=Corrected, type=Physical Layer, id=00e5 (Receiver ID)
    device [8086:9d15] error status/mask=00000001/00002000
    [ 0] Receiver Error          (First)
AER: Corrected error received: id=00e5
  can't find device of ID00e5

where "device [8086:9d15]" pointed to the Realtek RTL8723be adapter.

[JeremyB]

Do a

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sudo rm /etc/modprobe.d/rtl8723be.conf

Then try the signal test again

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sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=1
iwlist scan | egrep -i 'ssid|quality' 

sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=2
iwlist scan | egrep -i 'ssid|quality' 

The code may have changed so that 1 is better than 2 now. I tested the code a month or so ago with an old laptop with the rtl8723be that I removed one antenna wire from and it worked fine after using the github source. Another option is to remove the bottom panel from the laptop and switch the antenna wire from the one connector to the other.

I am not sure why you think [8086:9d15] is related to the wifi as the 8086 is an Intel device

[confuzzled]

Do a

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sudo rm /etc/modprobe.d/rtl8723be.conf

Then try the signal test again

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sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=1
iwlist scan | egrep -i 'ssid|quality' 

sudo modprobe -r rtl8723be
sudo modprobe rtl8723be ant_sel=2
iwlist scan | egrep -i 'ssid|quality' 

The code may have changed so that 1 is better than 2 now. I tested the code a month or so ago with an old laptop with the rtl8723be that I removed one antenna wire from and it worked fine after using the github source. Another option is to remove the bottom panel from the laptop and switch the antenna wire from the one connector to the other.

I am not sure why you think [8086:9d15] is related to the wifi as the 8086 is an Intel device

Hi,

I ran the signal test again and got the same result for both 1 & 2 (see below):

ant_sel=1

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enp1s0    Interface doesn't support scanning.
lo        Interface doesn't support scanning.
                    Quality=34/70  Signal level=-76 dBm  
                    ESSID:"------Net"

ant_sel=2

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enp1s0    Interface doesn't support scanning.
lo        Interface doesn't support scanning.
                    Quality=34/70  Signal level=-76 dBm  
                    ESSID:"------Net"

I tried to connect after running the test, with the network manager showing a signal strength of 40% (which went up to 47%, right after I clicked on my Wifi network). The connection failed with the notification: "Disconnected" and the network disappearing from the network manager.

1. I've seen, in other threads, suggestions to try installing the rock.new_btcoex drivers instead. Would that help or would it be ill-advised?

2. I've also found somebody saying that they replaced the Cinnamon network manager with the Wicd network manager, and that their rtl8723be adapter worked fine afterwards. Would that help or would it be ill-advised?

[JeremyB]

The rock it coex branch has been abandoned as that code was put in master branch years ago. I doubt using wicd will help as the kernel parameters determine what antenna is used
Post results for

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dkms status

[confuzzled]

The rock it coex branch has been abandoned as that code was put in master branch years ago. I doubt using wicd will help as the kernel parameters determine what antenna is used
Post results for

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dkms status

rtlwifi-new, 0.6: added

[confuzzled]

Ok, that's interesting. I just took my laptop and set it up right next to the router. I wanted to see if a stronger signal (now 58%) would make a difference. Well, it did; the laptop connected immediately over Wifi.

So the issue isn't that the laptop won't connect, but that it considers the signal too weak for it to connect. The laptop doesn't have this problem under Windows.

Update: my router sits downstairs and I work one floor up. After connecting downstairs, I took the laptop upstairs and the connection stayed alive (at 43-44%). So I disconnected and tried to reconnect. It took longer than downstairs but the connection was successfully re-established. I guess the problem might have resolved itself with that 1st successful connection.

[JeremyB]

Have you rebooted since installing from GitHub?
I am not sure why it says that rtlwifi was added but doesn't show as installed

[confuzzled]

Have you rebooted since installing from GitHub?

Yes, multiple times. In fact, I just did in order to see if the connection would get re-established after a shutdown. Unfortunately, it doesn't look like it worked; the connection failed again and the signal strength went down to 24% (from the same spot where it was previously showing 43-44%).

Update: and right before I was about to post the above, the signal went up to 40%+ and the laptop connected over Wifi.

Update 2: I shut down the laptop to try again. This time the connection failed and the network vanished from the network manager. BUT, after I plugged in the ethernet cable and the wired connection was established, I turned Wireless off & on and the laptop connected over Wifi almost immediately. Does this mean the adapter needs to be "activated" somehow before it will connect wirelessly?

Update 3: I shut the laptop down yet again (shutdown not restart), and this time the laptop connected quickly over Wifi, with no ethernet involved.

Update 4: after leaving the laptop on for a while (without using it), I returned to find the connection had gone down and the laptop would not connect again. But as before, once I plugged in the ethernet cable and established a wired connection, the Wifi connection was established in short order. Could the "activation" issue be a problem with the adapter's power management?

[JeremyB]

I just booted up my laptop with a Mint drive and it worked fine after using the github driver and the ant_sel=2 parameter
Lets deactivate some wifi power management

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sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

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echo "options rtl8723be ips=N" | sudo tee /etc/modprobe.d/rtl8723be-power.conf

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sudo dkms install rtlwifi-new/0.6

Reboot

[confuzzled]

I just booted up my laptop with a Mint drive and it worked fine after using the github driver and the ant_sel=2 parameter
Lets deactivate some wifi power management

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sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

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echo "options rtl8723be ips=N" | sudo tee /etc/modprobe.d/rtl8723be-power.conf

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sudo dkms install rtlwifi-new/0.6

Reboot

Alright, that seems to have worked. Upon reboot, the laptop connected immediately over Wifi. Thank you.

May I ask what the power management commands do & if there are any downsides to them?

[JeremyB]

The only downside to disabling power management is that you might use up battery power a little faster. Wifi power management causes a lot of issues when enabled

[confuzzled]

The only downside to disabling power management is that you might use up battery power a little faster. Wifi power management causes a lot of issues when enabled

Ok. Well, it seems I spoke too soon. Sorry. The screen saver came on after a period of inactivity and then the laptop wouldn't connect once again.

This is maddening. Now, even after a reboot and even after connecting over ethernet, the laptop just won't connect wirelessly anymore.

[JeremyB]

What happens

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cd rtlwifi_new
git status

[confuzzled]

What happens

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cd rtlwifi_new
git status

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On branch extended
Your branch is up to date with 'origin/extended'.

nothing to commit, working tree clean

[JeremyB]

Do

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cd
sudo dkms remove rtlwifi-new/0.6 --all
sudo dkms add ./rtlwifi_new
sudo dkms install rtlwifi-new/0.6

Reboot, hopefully the build source in /usr/src/rtlwifi-new-0.6 was just older and the current will fix this

[confuzzled]

Do

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cd
sudo dkms remove rtlwifi-new/0.6 --all
sudo dkms add ./rtlwifi_new
sudo dkms install rtlwifi-new/0.6

Reboot, hopefully the build source in /usr/src/rtlwifi-new-0.6 was just older and the current will fix this

Done. The laptop connected right away. Is there a "torture test" to see if the fix will stick?

I appreciate all your help.

[JeremyB]

I would check

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iwlist scan | egrep -i 'ssid|quality' 

To see if it is better than it was before

[confuzzled]

I would check

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iwlist scan | egrep -i 'ssid|quality' 

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lo        Interface doesn't support scanning.

enp1s0    Interface doesn't support scanning.

                    Quality=34/70  Signal level=-76 dBm  
                    ESSID:"---------Net"

Even though the reported quality / signal level are not better than before, the laptop successfully connected right away after another shutdown/restart, and also after I toggled Wireless Off & On.

Update: I've done 2 restarts, toggled the wireless Off & On twice, & put the computer to sleep, and the laptop has been able to connect wirelessly after each change. So I think that's finally done it, for good hopefully.

Update 2: it's been several hours now and the wireless connection hasn't gone down in all that time, so I think the problem's fixed for good.

Will software updates (such as kernel upgrades) modify any of the settings you had me implement (i.e. will I need to redo any of the steps above after an upgrade/update)?

Once again thank you for all your help.

Update 3: it's now a day later and the problems which I thought had been solved have returned, so I am unmarking this as solved. I truly appreciate JeremyB taking the time to help me out, but at this point, it's pretty clear that the Realtek RTL8723be adapter is unadulterated junk and (given the number of threads about it in this and other forums) just doesn't work under Linux.