New wifi connection eeach boot

My Network Manager has recently started to create a wifi connection on every reboot. I’m currently up to wlan28 (from wlan0, of course). It means inputting the router password each time to restart wifi, which of course is doable fairly quickly but a total pain.
I’m on framework 5.78 and plasma 5.20.5.
It seems like a bug but I’m not sure how to handle it.
Anyone have any ideas?

While this should not happen of course, I do not think that NM is to blame. The device names are given by the system (udev).
This to avoid searching for a solution in the wrong place.

Read:
https://bugs.launchpad.net/ubuntu/+source/udev/+bug/153727

I was affected by the same bug on wlan a few years ago, I have done something, but I do not know it anymore.

But it has to do with udev…

A case of MAC spoofing? MAC spoofing - Wikipedia

See the part about MAC Address Randomization in WiFi.

I’m not much wiser but thanks for the responses. I added wifi.scan-rand-mac-address=no to Networkmanager.conf some time ago because I thought that stops it. Maybe I’ve got that the wrong way round.
I’m now up to wlan32.

You can edit this file and delete all the wlan entries

sudo vi /etc/udev/rules.d/70-persistent-net.rules

Thanks. I’d already done that and started back at wlan0. This morning I’m at wlan1.
So I’m back where I started. Maybe I’ll just live with it and see if it corrects itself with future updates.

I’ve been looking at this further and the mac address remains the same throughout. Only the device name changes, incremented by 1 each time. Having restarted I’m now on wlan4.

The wrong way to fix it but it should work!!!

step 1 sudo vi /etc/udev/rules.d/70-persistent-net.rules and delete all but wlan0

step 2 sudo chmod 444 /etc/udev/rules.d/70-persistent-net.rules - make it so that it cannot be changed (it should be 644)

now it cannot be added to any more.

to undo just sudo chmod 644 /etc/udev/rules.d/70-persistent-net.rules

For 45 years my job was to get Unix/Linux working - sometime the fix is just plain UGLY. Then you wait for the proper fix.

Strange…of course it is /usr/lib/udev/rules.d/75-persistent-net-generator.rules that is triggered (eg usually a new device with unique MAC) and subsequently creates the new entries. It would have been interesting to see the multiple entries, and the associated MACs.

Example…

# PCI device 0x8086:0x100e (e1000)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="08:00:27:74:e4:b1", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

# PCI device 0x8086:0x100e (e1000)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="08:00:27:8f:eb:84", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

Actually, I was wrong. The last 3 sets in the mac address change. The first 3 remain the same and it was a quick glance that made me think they weren’t changing.

Yes, that makes sense.