How to manually install WiFi firmware on Debian Live?

Cmdte Alpha Tigre Z

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Mar 11, 2021, 7:40:05 PM3/11/21

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Hello.

I tried to make a "Realtek RTL8191SU Wireless LAN 802.11n USB 2.0
Network Adapter" work on Debian 10 Live with LXDE, but I couldn't.
Here is what I already have tried:

1-. Downloaded package firmware-realtek from package.debian.org.
2-. Booted Debian Live.
3-. Copied package from hard disk to the desktop (apt complains when
I load it directly).
4-. Executed: sudo apt install firmware-realtek
5-. Executed: sudo depmod -a
6-. Executed: sudo modprobe r8712u

Then, Wicd didn't show anything. I ran udevadm, I don't remember how,
to see if the USB WiFi adapter was detected; it was and also
the module r8712u was loaded for it.

I need some help here, please. I don't want to use a non-free firmware
live image. Thanks.

IL Ka

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Mar 11, 2021, 8:00:05 PM3/11/21

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1-. Downloaded package firmware-realtek from package.debian.org.
2-. Booted Debian Live.
3-. Copied package from hard disk to the desktop (apt complains when
I load it directly).
4-. Executed: sudo apt install firmware-realtek
5-. Executed: sudo depmod -a
6-. Executed: sudo modprobe r8712u

Lets see if driver was able to run your card:

Check output of

$ lspci

$ iw dev

$ ip link show

If everything is ok, check if your card can see any network

$ iw dev [YOUR_CARD_DEVICE] scan

(I do not remember exact syntax, try "man iw" or "iw help")

There is a good tutorial here: https://wiki.debian.org/WiFi/HowToUse

Charles Curley

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Mar 11, 2021, 10:40:04 PM3/11/21

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On Thu, 11 Mar 2021 20:38:04 -0400
Cmdte Alpha Tigre Z <santia...@gmail.com> wrote:

> I tried to make a "Realtek RTL8191SU Wireless LAN 802.11n USB 2.0
> Network Adapter" work on Debian 10 Live with LXDE, but I couldn't.
> Here is what I already have tried:
>
> 1-. Downloaded package firmware-realtek from package.debian.org.

Erm, possibly because firmware-realtek doesn't support that particular
adapter (??). It supports variants of the 8191, but I don't see the SU.

root@orca:~# apt-cache show firmware-realtek | grep -i RTL8191SU
root@orca:~# apt-cache show firmware-realtek | grep -i RTL8191
* Realtek RTL8192SE/RTL8191SE firmware, version 4.816.2011
root@orca:~#

I say, possibly, because Realtek firmware is screwy.

There are also USB WiFi adapters that simply don't play with Linux.

--
Does anybody read signatures any more?

https://charlescurley.com
https://charlescurley.com/blog/

Anssi Saari

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Mar 12, 2021, 4:20:04 AM3/12/21

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IL Ka <kazakev...@gmail.com> writes:

> 1-. Downloaded package firmware-realtek from package.debian.org.
> 2-. Booted Debian Live.
> 3-. Copied package from hard disk to the desktop (apt complains when
> I load it directly).
> 4-. Executed: sudo apt install firmware-realtek
> 5-. Executed: sudo depmod -a
> 6-. Executed: sudo modprobe r8712u
>
> Lets see if driver was able to run your card:
>
> Check output of
> $ lspci

lsusb is going to be more useful with a USB device.

Cmdte Alpha Tigre Z

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Mar 12, 2021, 8:10:05 AM3/12/21

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Here are some corrections, I did not really run these commands that way.

2021-03-11 20:38 GMT-04:00, Cmdte Alpha Tigre Z <santia...@gmail.com>:
> 4-. Executed: sudo apt install firmware-realtek

sudo apt install <path-to-firmware-realtek>

> 5-. Executed: sudo depmod -a

sudo /sbin/depmod -a

> 6-. Executed: sudo modprobe r8712u

sudo /sbin/modprobe r8712u

2021-03-11 20:55 GMT-04:00, IL Ka <kazakev...@gmail.com>:
> Lets see if driver was able to run your card:
>
> Check output of
> $ lspci

bash: lspci: command not found :)
It was not under /bin nor /sbin

> $ iw dev

This didn't show anything

> $ ip link show

user@debian:/sbin$ ./ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp0s25: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc
pfifo_fast state DOWN mode DEFAULT group default qlen 1000
link/ether 00:1e:4f:d6:1e:70 brd ff:ff:ff:ff:ff:ff

> If everything is ok, check if your card can see any network
>
> $ iw dev [YOUR_CARD_DEVICE] scan

There are no devices so I didn't run this.

2021-03-12 5:16 GMT-04:00, Anssi Saari <a...@sci.fi>:
> lsusb is going to be more useful with a USB device.

bash: lsusb: command not found
:)

2021-03-11 23:14 GMT-04:00, Charles Curley <charle...@charlescurley.com>:
> Erm, possibly because firmware-realtek doesn't support that particular
> adapter (??). It supports variants of the 8191, but I don't see the SU.
>

> I say, possibly, because Realtek firmware is screwy.

I don't know:
https://wiki.debian.org/rtl819x
https://wiki.debian.org/rtl819x#supported-r8712u

> There are also USB WiFi adapters that simply don't play with Linux.

I wish this is not the case.

Brian

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Mar 12, 2021, 9:10:04 AM3/12/21

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On Thu 11 Mar 2021 at 20:38:04 -0400, Cmdte Alpha Tigre Z wrote:

> Hello.
>
> I tried to make a "Realtek RTL8191SU Wireless LAN 802.11n USB 2.0
> Network Adapter" work on Debian 10 Live with LXDE, but I couldn't.
> Here is what I already have tried:
>
> 1-. Downloaded package firmware-realtek from package.debian.org.

Ok. May also be done with 'apt download firmware-realtek'.

> 2-. Booted Debian Live.
> 3-. Copied package from hard disk to the desktop (apt complains when
> I load it directly).
> 4-. Executed: sudo apt install firmware-realtek

I think that is incorrect. If you are in the same directory as
firmware-realtek, I'd do 'sudo apt install ./firmware-realtek'.

> 5-. Executed: sudo depmod -a
> 6-. Executed: sudo modprobe r8712u

According to

https://wiki.debian.org/rtl819x#Realtek_RTL8188CE.2C_RTL8188CUS.2C_RTL8188DE.2C_RTL8188EE.2C_RTL8188ETV.2C_RTL8188EU.2C_RTL8188SU.2C_RTL8191SE.2C_RTL8191SU.2C_RTL8192CE.2C_RTL8192CU.2C_RTL8192DE.2C_RTL8192E.2C_RTL8192EE.2C_RTL8192SE.2C_RTL8192SU.2C_RTL8192U.2C_RTL8723AE.2C_RTL8723AU.2C_RTL8723BE.2C_RTL8812AE.2C_RTL8821AE_devices

this is the correct kernel module.

> Then, Wicd didn't show anything. I ran udevadm, I don't remember how,
> to see if the USB WiFi adapter was detected; it was and also
> the module r8712u was loaded for it.
>
> I need some help here, please. I don't want to use a non-free firmware
> live image. Thanks.

'ip a' should show all available interfaces.

--
Brian.

Brian

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Mar 12, 2021, 9:30:05 AM3/12/21

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On Fri 12 Mar 2021 at 14:04:14 +0000, Brian wrote:

> On Thu 11 Mar 2021 at 20:38:04 -0400, Cmdte Alpha Tigre Z wrote:
>
> > 4-. Executed: sudo apt install firmware-realtek
>
> I think that is incorrect. If you are in the same directory as
> firmware-realtek, I'd do 'sudo apt install ./firmware-realtek'.

Correction:

sudo apt install ./firmware-realtek_20190114-2_all.deb

--
Brian.

Cmdte Alpha Tigre Z

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Mar 12, 2021, 11:30:05 AM3/12/21

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Yes, thanks for noting it. This is what I wrote here:

El vie, 12 mar 2021 a las 9:00, Cmdte Alpha Tigre Z
(<santia...@gmail.com>) escribió:

> Here are some corrections, I did not really run these commands that way.
>
> 2021-03-11 20:38 GMT-04:00, Cmdte Alpha Tigre Z <santia...@gmail.com>:

> > 4-. Executed: sudo apt install firmware-realtek
>

> sudo apt install <path-to-firmware-realtek>

<path-to-firmware-realtek> is
/home/user/Desktop/firmware-realtek_20190114-2_all.deb

El vie, 12 mar 2021 a las 10:04, Brian (<ad...@cityscape.co.uk>) escribió:
>
> On Thu 11 Mar 2021 at 20:38:04 -0400, Cmdte Alpha Tigre Z wrote:

> > I tried to make a "Realtek RTL8191SU Wireless LAN 802.11n USB 2.0
> > Network Adapter" work on Debian 10 Live with LXDE, but I couldn't.
> > Here is what I already have tried:
> >
> > 1-. Downloaded package firmware-realtek from package.debian.org.
>
> Ok. May also be done with 'apt download firmware-realtek'.

That would work if I already had Debian with internet connection.
I can't use apt for anything because I don't have WiFi connection.

El vie, 12 mar 2021 a las 10:04, Brian (<ad...@cityscape.co.uk>) escribió:
> 'ip a' should show all available interfaces.

Ok, I'll try that.

Anssi Saari

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Mar 12, 2021, 1:20:05 PM3/12/21

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Cmdte Alpha Tigre Z <santia...@gmail.com> writes:

> Hello.
>
> I tried to make a "Realtek RTL8191SU Wireless LAN 802.11n USB 2.0
> Network Adapter" work on Debian 10 Live with LXDE, but I couldn't.
> Here is what I already have tried:
>
> 1-. Downloaded package firmware-realtek from package.debian.org.
> 2-. Booted Debian Live.
> 3-. Copied package from hard disk to the desktop (apt complains when
> I load it directly).
> 4-. Executed: sudo apt install firmware-realtek
> 5-. Executed: sudo depmod -a
> 6-. Executed: sudo modprobe r8712u
>
> Then, Wicd didn't show anything. I ran udevadm, I don't remember how,
> to see if the USB WiFi adapter was detected; it was and also
> the module r8712u was loaded for it.

udevadm trigger is the command to run to simulate plugging in the wifi
adapter after you have the firmware available. I don't think modprobe
loads firmware.

Alternatively you can just unplug and plug the adapter after installing
the firmware.

But if you did this and it still doesn't work I'm pretty much out of
ideas. Does dmesg report anything relevant to network or realtek? For
example I get this when my new system boots:

r8169 0000:03:00.0: firmware: direct-loading firmware rtl_nic/rtl8125b-2.fw

deloptes

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Mar 12, 2021, 6:20:05 PM3/12/21

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Anssi Saari wrote:

> udevadm trigger is the command to run to simulate plugging in the wifi
> adapter after you have the firmware available. I don't think modprobe
> loads firmware.

loading the driver, loads the firmware
unloading the driver, unloads the firmware

both done with modprobe. How do you load firmware manually, please?

David Wright

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Mar 12, 2021, 7:20:04 PM3/12/21

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I've always assumed that each driver (module) knows how to load
its own firmware into its own hardware in its own special way.
I've never tried going back and forth, but even if the firmware
remains in the device, there's little to be gained by not reloading
it, and a lot more to be gained by refreshing it (like updating it).

Cheers,
David.

Anssi Saari

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Mar 13, 2021, 3:10:04 AM3/13/21

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deloptes <delo...@gmail.com> writes:

> Anssi Saari wrote:
>
>> udevadm trigger is the command to run to simulate plugging in the wifi
>> adapter after you have the firmware available. I don't think modprobe
>> loads firmware.
>
> loading the driver, loads the firmware
> unloading the driver, unloads the firmware

> both done with modprobe.

Are they? Show me. What I'm saying is modprobe doesn't load firmware and
udev does since that was the observed behavior here. The OP in this very
thread installed firmware and modprobed the driver but wifi device still
didn't work.

> How do you load firmware manually, please?

I don't know, feel free look it up and share. All I know there was once
a specific command to load fw for an old 3G modem I have in an old
laptop but today that seems to happen automatically.

Tixy

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Mar 13, 2021, 5:10:05 AM3/13/21

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On Sat, 2021-03-13 at 10:04 +0200, Anssi Saari wrote:
> deloptes <delo...@gmail.com> writes:
>
> > Anssi Saari wrote:
> >
> > > udevadm trigger is the command to run to simulate plugging in the wifi
> > > adapter after you have the firmware available. I don't think modprobe
> > > loads firmware.
> >
> > loading the driver, loads the firmware
> > unloading the driver, unloads the firmware
>
> > both done with modprobe.
>
> Are they? Show me. What I'm saying is modprobe doesn't load firmware and
> udev does since that was the observed behavior here.

That doesn't seem to be the standard method for the last 9 years,
see...

https://lwn.net/Articles/518942/
https://lkml.org/lkml/2013/8/5/175

>From reading those it appears that if firmware is in the correct
filesystem location, then user space won't be involved any more with
its loading.

Maybe the old ways are still enabled in Debian and used in some cases?
My bullseye kernel does have the kernel config enabled for user side
firmware loaders, I've not looked at udev.

--
Tixy

Anssi Saari

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Mar 15, 2021, 12:50:05 PM3/15/21

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Tixy <ti...@yxit.co.uk> writes:

> That doesn't seem to be the standard method for the last 9 years,
> see...
>
> https://lwn.net/Articles/518942/
> https://lkml.org/lkml/2013/8/5/175

Thanks.

> Maybe the old ways are still enabled in Debian and used in some cases?
> My bullseye kernel does have the kernel config enabled for user side
> firmware loaders, I've not looked at udev.

I seriously doubt that. udev is part of systemd now and it seems crazy
Debian would maintain old code like that. With a quick look at the the
patches Debian applies to udev there are six but none of them seem
relevant to firmware loading.

Kenneth Parker

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Mar 15, 2021, 1:10:04 PM3/15/21

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That brings up a question: Do Debian and Devuan (Debian fork without SystemD) use the same Kernels?

(And I may be able to answer my own question when I get home, as I run both).

Kenneth Parker

Anssi Saari

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Mar 15, 2021, 4:50:04 PM3/15/21

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Kenneth Parker <sea7...@gmail.com> writes:

> That brings up a question: Do Debian and Devuan (Debian fork without SystemD) use the same Kernels?
>
> (And I may be able to answer my own question when I get home, as I run both).

At least the versions look similar, 4.19 in stable and 5.10 from
backports.

Kenneth Parker

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Mar 15, 2021, 11:50:05 PM3/15/21

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I didn't find what I was looking for (same Kernel in Debian and Devuan, where I could compare files) but, as Anssi found, they seem to come from the same place.

Kenneth Parker