Shahriar Al Rabbi
Posts: 3
Joined: Mon May 14, 2018 9:53 am

"sudo ifup wlan0" shows "unknown interface wlan0"

Mon May 14, 2018 10:00 am

"sudo ifup wlan0" shows "unknown interface wlan0"
In the desktop, the internet connectivity logo, ethernet works fine but shows "no wireless device detected.
I installed the April 2018 raspbian stretch properly and still doesn't work.

If there is a solution, please let me know.
Or the product might have been damaged before it came to me.

"ifconfig" shows "eth0", "lo" as well as "wlan0" .
So, there might be a solution.

copperly
Posts: 2
Joined: Wed Aug 09, 2017 11:40 pm

RE: "sudo ifup wlan0" shows "unknown interface wlan0"

Mon May 14, 2018 12:45 pm

I second that motion

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mahjongg
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Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Mon May 14, 2018 12:52 pm

Split off from topic marked [SOLVED]

MrEngman
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Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Mon May 14, 2018 1:39 pm

Try these

Code: Select all

sudo ip link set wlan0 down
sudo ip link set wlan0 up
Simplicity is a prerequisite for reliability. Edsger W. Dijkstra

Please post ALL technical questions on the forum. Please Do Not send private messages.

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PeterO
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Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Mon May 14, 2018 1:54 pm

Try running "ifconfig" to see
a) if the interfaces exist
b) What they are called.

PeterO
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Cowpoke
Posts: 3
Joined: Sun Nov 20, 2016 9:25 pm

Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Sun Jul 08, 2018 2:20 pm

Finally, are the ifup and ifdown commands obsolete?

SurferTim
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Location: Miramar Beach, Florida

Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Sun Jul 08, 2018 2:21 pm

Cowpoke wrote:
Sun Jul 08, 2018 2:20 pm
Finally, are the ifup and ifdown commands obsolete?
Yes.
My advice applies to RaspiOS only. Please mention if you use another OS.

rohtua
Posts: 71
Joined: Sat Jul 16, 2016 9:01 am

Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Mon Jul 09, 2018 10:02 am

Hi, I had some similar problems a while ago on a fresh raspbian install I think what sorted it for me in the end was the Wi-Fi localisation options in raspi-config, when I looked I'd set the timezone options but now you get separate options for setting your Wi-Fi country. Might not do a lot but if I remember rightly it did help with the issues I was having at the time.

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HermannSW
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Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Fri Sep 07, 2018 2:56 pm

MrEngman wrote:
Mon May 14, 2018 1:39 pm
Try these

Code: Select all

sudo ip link set wlan0 down
sudo ip link set wlan0 up
Thank you, that worked for me while ifup did not.

Pi ZeroW was connected to ESP-01s module access point. For some reason the connection dropped and "ip link show" showed wlan0 in DORMANT state. First I tried only your 2nd command, that did not help. But running both did work!
https://stamm-wilbrandt.de/2wheel_balancing_robot
https://stamm-wilbrandt.de/en#raspcatbot
https://github.com/Hermann-SW/Raspberry_v1_camera_global_external_shutter
https://github.com/Hermann-SW/raspiraw
https://stamm-wilbrandt.de/en/Raspberry_camera.html

OutsourcedGuru
Posts: 66
Joined: Mon Jun 19, 2017 11:15 pm

Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Wed Dec 18, 2019 9:26 pm

If both ifup and ifdown are now obsolete, you might consider removing their respective man pages and executables so that you don't fool someone like myself. As it is, the command is present and indicates:

Code: Select all

ifup: unknown interface wlan0
...rather than the expected:

Code: Select all

sudo: ifup: command not found

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rpdom
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Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Wed Dec 18, 2019 9:48 pm

OutsourcedGuru wrote:
Wed Dec 18, 2019 9:26 pm
If both ifup and ifdown are now obsolete, you might consider removing their respective man pages and executables so that you don't fool someone like myself.
The proper way to do that would be to remove the ifupdown package. I'm not sure why it is still installed. Perhaps something in it is still required?
Unreadable squiggle

SageDesign
Posts: 20
Joined: Wed Jan 09, 2013 2:19 pm

Re: "sudo ifup wlan0" shows "unknown interface wlan0"

Thu May 14, 2020 3:48 pm

I am trying to build a cluster of 5 Pis, 3 x 3B+ and 2 x Pi4, using a SKY SR102 wireless router to connect them. Not going smoothly: the 3Bs are happy and connect, but the 2 x 4s will not connect, even though their setups appear to be identical. I cannot persuade them to connect, using ifup (?) or "set wlan0 up". They will occasionally connect, for no known reason. Any ideas please?

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