Ethernet keeps connecting/disconnecting until it finally connects by miracle

Hello,

It has been a few month already since I had this bug, but it’s getting out of hand recently. When I startup + login, the WiFi is connected immediatly, but the ethernet keeps trying to connect, disconnect, re-connect… and it can do that for 5-10 minutes! When finally, after that time, the connection is made.

I already tried to disable IPv6, but the issue is still there. I had no issue in the beggining of the last year (maybe different kernel), and it’s not happening on Windows (dual boot).

Here what the log says:

journalctl -b --no-hostname --no-pager -u NetworkManager
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.8310] policy: auto-activating connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.8322] device (eno2): Activation: starting connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.8325] device (eno2): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.9434] device (eno2): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.9451] device (eno2): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:22 NetworkManager[559]: <info>  [1646213962.9456] dhcp4 (eno2): activation: beginning transaction (timeout in 45 seconds)
mars 02 10:39:28 NetworkManager[559]: <info>  [1646213968.9452] device (eno2): state change: ip-config -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed')
mars 02 10:39:28 NetworkManager[559]: <info>  [1646213968.9645] dhcp4 (eno2): canceled DHCP transaction
mars 02 10:39:28 NetworkManager[559]: <info>  [1646213968.9646] dhcp4 (eno2): state changed unknown -> terminated
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.7257] device (eno2): carrier: link connected
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.7262] device (eno2): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.7277] policy: auto-activating connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.7287] device (eno2): Activation: starting connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.7289] device (eno2): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.8401] device (eno2): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.8417] device (eno2): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:34 NetworkManager[559]: <info>  [1646213974.8423] dhcp4 (eno2): activation: beginning transaction (timeout in 45 seconds)
mars 02 10:39:40 NetworkManager[559]: <info>  [1646213980.8420] device (eno2): state change: ip-config -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed')
mars 02 10:39:40 NetworkManager[559]: <info>  [1646213980.8521] dhcp4 (eno2): canceled DHCP transaction
mars 02 10:39:40 NetworkManager[559]: <info>  [1646213980.8521] dhcp4 (eno2): state changed unknown -> terminated
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.5990] device (eno2): carrier: link connected
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.5995] device (eno2): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.6009] policy: auto-activating connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.6019] device (eno2): Activation: starting connection 'Ethernet' (7e510ab4-383a-3c73-bbde-9089570e24e2)
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.6021] device (eno2): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.7097] device (eno2): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.7106] device (eno2): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
mars 02 10:39:46 NetworkManager[559]: <info>  [1646213986.7108] dhcp4 (eno2): activation: beginning transaction (timeout in 45 seconds)
mars 02 10:39:52 NetworkManager[559]: <info>  [1646213992.7109] device (eno2): state change: ip-config -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed')
mars 02 10:39:52 NetworkManager[559]: <info>  [1646213992.7285] dhcp4 (eno2): canceled DHCP transaction
mars 02 10:39:52 NetworkManager[559]: <info>  [1646213992.7286] dhcp4 (eno2): state changed unknown -> terminated

It keeps repetting theses lines as long as it doesn’t work, until it works:

mars 02 10:42:45 NetworkManager[559]: <info>  [1646214165.5249] dhcp4 (eno2): activation: beginning transaction (timeout in 45 seconds)
mars 02 10:42:51 NetworkManager[559]: <info>  [1646214171.1619] device (eno2): carrier: link connected
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.4530] dhcp4 (eno2): state changed unknown -> bound, address=192.168.1.17
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.4544] device (eno2): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.4709] device (eno2): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.4712] device (eno2): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.4761] device (eno2): Activation: successful, device activated.
mars 02 10:42:54 NetworkManager[559]: <info>  [1646214174.5846] policy: set 'Ethernet' (eno2) as default for IPv4 routing and DNS

Do you have any idea?

Thanks

inxi -nz

and

systemctl status dhcp*

?

Hello,

inxi -nz :

Unescaped left brace in regex is passed through in regex; marked by <-- HERE in m/^${ <-- HERE PATH}$/ at /usr/bin/inxi line 553.
Network:
  Device-1: Intel Cannon Lake PCH CNVi WiFi driver: iwlwifi
  IF: wlo1 state: up mac: <filter>
  Device-2: Intel Ethernet I219-V driver: e1000e
  IF: eno2 state: up speed: 1000 Mbps duplex: full mac: <filter>

And the last command about dhcp returns nothing, but as the computer still manage to connect some minutes after trying, not sure if it’s the issue (I have dhcpcd installed)?

There is some inconistency here - the driver listed being wirelies but you are refering an ethernet driver - what is what?

I admit I am not on the latest and greatest but it seems a little off to me.

I have both WiFi and Ethernet on my computer. But I’m referring the ethernet one (device-2). The WiFi has no problems.

Turn off or otherwise disable the wireless device.

Before that bug, I wasn’t using WiFi it was always disabled on Network Manager. If I enabled it today, it’s to be able to use internet without waiting 10 minutes that Ethernet finally work (even with wifi off the bug is here)

Is it possible your ethernet cable is faulty? (it could be old, got bent, poor connection)
Can you try another cable?

2 Likes

What happens if you disable the wireless in your system BIOS?

No I already changed them (was cat 5, now cat 7), no change. Tried several without success. And anyway it works without issue on Windows on the same computer so I’m pretty sure that not the issue here

Hello,

It changes nothing too. The thing is that it used to work with older kernel (or older packages I dont know) and still works on Windows with both activated. It’s also not coming from the ethernet cable as I tried several, so it seems to be more software related.

In the past one of the trick was to put manually the ethernet to 100 mbps instead of automatic, and disable ipv6. But nowadays, this doesn’t work anymore.

So I here is two questions:

  1. If i downgrade to a pretty older kernel, won’t things break
  2. Should I use dhcp package instead of dhcpcd?

I don’t have too many ideas; my iPads are the only WiFi in use here; both of my desktops have no wireless (WiFi/bluetooth) capability at all.

However:

Your OP shows

So you shouldn’t be using any external DHCP client; that’s why I asked you for

Pick one. Don’t run any others.

Hello,

That command returns nothing, so I guess nothing else is running… I’ll remove the package and see if it’s better in the next days.

So I can confirm that I still change nothing. I still have the same issue even with dhcpcd rermoved (it’s just a bit shorter, but maybe it’s just random).

I don’t have any other ideas; short of disabling any/all Network Manager(s), and using plain dhcpcd or dhclient to compare results.