[SOLVED] Yet another tethering thread

[Don B. Cilly]

I'm trying to see whether I could use my Android phone's connection to have internet access in case my router broke down (they do) while I was waiting for a replacement.

So what I do is, connect the phone to the PC via USB, go into the phone's network settings, turn Tethering on.
Immediately, a "Wired connection 2" is activated on the PC. Immediately after that - ~1 second, it disappears.
What (else) should I try?

[claydoh]

That's how I do it, works as expected here. I use an LG V30, but it has always worked for me on my previous phones.
I do usually use wireless tethering, though. Simpler and can use it with any of my devices.
I doubt it is an issue where you live, but could it be your carrier doesn't allow tethering, without an extra charge, or a plan that supports it?

[Don B. Cilly]

This is also an LG, it's called a K11 in Spain, something else elsewhere...
Wireless tethering, it's a desktop, even though I do have a WIFI dongly-thingy for it somewhere.
Still, to check if it works, USB will do.

Now, if "my carrier doesn't allow tethering, without an extra charge"... I'll try and find out, but would it behave that way if it were the case?
Network interface appearing for a second and then vanishing, I mean.

[EDIT] From what I can find, there are no restrictions on tethering for my carrier and country.

[GreyGeek]

I have used tethering with my Samsung Galaxy S10 a few weeks ago, but with so many updates on my 20.04 I decided to try it again.

My first test was using USB tethering to my USB 3.0 port. It didn't work. So, I plugged it into my USB 2.0 hub and I got a beautiful 30Mbps connection (that's as fast as Sprint is in this area, but as a bonus my connection was IPv6 !)

Then I tried a Bluetooth connection. It immediately connected and then disconnected. That is because I have to open the Network Manager Configuration UI, create a new "Mobile Broadband" connection, select cdma from the dropdown combo (it defaults to gsm), select the United States region, select Sprint as the carrier and then enter the user name and password Sprint assigned me for bluetooth mobile hotspots. I did not have to do that for a USB tethered connection. But, I don't use Bluetooth on my smartphone. I keep it turned off.

[claydoh]

When I was on a different carrier here, Verizon I think, it would do this, no warning or messages. Just cut off almost instantly after connecting. But this was a few years ago.

Try a different cable if possible, that can have an effect, and possibly try turning wifi off on the phone, if it is enabled.
Also, this might work:
https://askubuntu.com/questions/7779...-disconnecting
it is for older version, but the cause could be similar and may be specific to LG phones, One user mentions an LG G4, which I myself still have, and used it specifically for tethering last year when I was in Australia, though mainly using wifi. I did test USB, though. to see which was more reliable. It worked, without the issues mentioned in the link, but wifi was just as reliable so I used the G4 as my portable internet for my V30 and whatever else we had.

[Don B. Cilly]

So, I had it connected to a USB 3.0. I tried with a 2.0. No luck.
I tried disabling WIFI. No luck.
I tried sudo systemctl stop ModemManager.service (per claydoh's link). Bingo

I tested it.
Latency: 146.8 ms
Download: 31.01 Mbps
Transferred Data: 79% 67.72 MB
Upload: 26.81 Mbps
Transferred Data: 24% 24.97 MB

Not too bad.
It was still on the 2.0 port. I connected it to a 3.0 one. It worked, but the test results were slightly worse :·/

[EDIT] I tested my fibre one. Latency: 122.9 ms. Download: 84.07 Mbps, Upload 82.75 Mbps, TD 94% and 74%.
Even though my conky was saying over 120 Mbps...