Kubuntu 26.04 Network device not working/showing after update or reboot

[cherryForge]

thanks for correcting my mistake.

xxx@xxx:~$ ls -l /vmlinuz* /initrd.img*
ls: cannot access '/vmlinuz*': No such file or directory
ls: cannot access '/initrd.img*': No such file or directory



xxx@xxx:~$ sudo apt update && sudo apt full-upgrade
Ign:1 http://security.ubuntu.com/ubuntu resolute-security InRelease
Ign:2 http://de.archive.ubuntu.com/ubuntu resolute InRelease
Ign:3 http://de.archive.ubuntu.com/ubuntu resolute-updates InRelease
Ign:4 http://de.archive.ubuntu.com/ubuntu resolute-backports InRelease
Ign:1 http://security.ubuntu.com/ubuntu resolute-security InRelease
Ign:4 http://de.archive.ubuntu.com/ubuntu resolute-backports InRelease
Ign:3 http://de.archive.ubuntu.com/ubuntu resolute-updates InRelease
Ign:2 http://de.archive.ubuntu.com/ubuntu resolute InRelease
Ign:1 http://security.ubuntu.com/ubuntu resolute-security InRelease
Ign:2 http://de.archive.ubuntu.com/ubuntu resolute InRelease
Ign:3 http://de.archive.ubuntu.com/ubuntu resolute-updates InRelease
Ign:4 http://de.archive.ubuntu.com/ubuntu resolute-backports InRelease
Fehl:1 http://security.ubuntu.com/ubuntu resolute-security InRelease
Temporärer Fehlschlag beim Auflösen von »security.ubuntu.com«
Fehl:4 http://de.archive.ubuntu.com/ubuntu resolute-backports InRelease
Temporärer Fehlschlag beim Auflösen von »de.archive.ubuntu.com«
Fehl:3 http://de.archive.ubuntu.com/ubuntu resolute-updates InRelease
Temporärer Fehlschlag beim Auflösen von »de.archive.ubuntu.com«
Fehl:2 http://de.archive.ubuntu.com/ubuntu resolute InRelease
Temporärer Fehlschlag beim Auflösen von »de.archive.ubuntu.com«
Alle Pakete sind aktuell.
Warnung: Fehlschlag beim Holen von http://de.archive.ubuntu.com/ubuntu/...lute/InRelease Temporärer Fehlschlag beim Auflösen von »de.archive.ubuntu.com«
Warnung: Fehlschlag beim Holen von http://de.archive.ubuntu.com/ubuntu/...ates/InRelease Temporärer Fehlschlag beim Auflösen von »de.archive.ubuntu.com«
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Warnung: Einige Indexdateien konnten nicht heruntergeladen werden. Sie wurden ignoriert oder alte an ihrer Stelle benutzt.
Get another security update through Ubuntu Pro with 'esm-apps' enabled:
libopenexr-3-1-30
Learn more about Ubuntu Pro at https://ubuntu.com/pro
Zusammenfassung:
Aktualisiere: 0, Installiere: 0, Entferne: 0, Aktualisiere nicht: 0
4 nicht vollständig installiert oder entfernt.
Benötigter Platz: 0 B / 57,7 GB verfügbar

Fortfahren? [J/n] j
linux-image-7.0.0-22-generic (7.0.0-22.22) wird eingerichtet ...
Failed to create symlink to vmlinuz-7.0.0-14-generic: Operation not permitted at /usr/bin/linux-update-symlinks line 64.
dpkg: Fehler beim Bearbeiten des Paketes linux-image-7.0.0-22-generic (--configure):
»altes postinst-Betreuerskript des Paketes linux-image-7.0.0-22-generic«-Unterprozess mit Exit-Status 1 fehlgeschlagen
dpkg: Abhängigkeitsprobleme verhindern Konfiguration von linux-image-generic:
linux-image-generic hängt ab von linux-image-7.0.0-22-generic; aber:
Paket linux-image-7.0.0-22-generic ist noch nicht konfiguriert.

dpkg: Fehler beim Bearbeiten des Paketes linux-image-generic (--configure):
Abhängigkeitsprobleme - verbleibt unkonfiguriert
dpkg: Abhängigkeitsprobleme verhindern Konfiguration von linux-generic:
linux-generic hängt ab von linux-image-generic (= 7.0.0-22.22); aber:
Paket linux-image-generic ist noch nicht konfiguriert.

dpkg: Fehler beim Bearbeiten des Paketes linux-generic (--configure):
Abhängigkeitsprobleme - verbleibt unkonfiguriert
dpkg: Abhängigkeitsprobleme verhindern Konfiguration von linux-main-modules-zfs-7.0.0-22-generic:
linux-main-modules-zfs-7.0.0-22-generic hängt ab von linux-image-7.0.0-22-generic | linux-image-unsigned-7.0.0-22-generic; aber:
Paket linux-image-7.0.0-22-generic ist noch nicht konfiguriert.
Paket linux-image-unsigned-7.0.0-22-generic ist nicht installiert.

dpkg: Fehler beim Bearbeiten des Paketes linux-main-modules-zfs-7.0.0-22-generic (--configure):
Abhängigkeitsprobleme - verbleibt unkonfiguriert
Es wurde kein Apport-Bericht verfasst, da die Fehlermeldung darauf hindeutet, dass dies lediglich ein Folgefehler eines vorherigen Problems ist.
Es wurde kein Apport-Bericht verfasst, da die Fehlermeldung darauf hindeutet, dass dies lediglich ein Folgefehler eines vorherigen Problems ist.
Es wurde kein Apport-Bericht verfasst, da das Limit MaxReports bereits erreicht ist.
Fehler traten auf beim Bearbeiten von:
linux-image-7.0.0-22-generic
linux-image-generic
linux-generic
linux-main-modules-zfs-7.0.0-22-generic
Fehler: Sub-process /usr/bin/dpkg returned an error code (1)

So im running Linux 7.0.0-14-generic? Because of that there is no older Kernel to choose.
And somehow the unsucsesfull update messing with networkcard settings.

I think I try a fresh install on weekend.

[die.boer]

output of

ls -l /boot

and also

sudo modprobe -r alx && sudo modprobe alx && sleep 3 && sudo ethtool enp2s0

[cherryForge]

xxx@xxx:~$ ls -l /boot
total 146760
-rwxr-xr-x 1 root root 11001551 Apr 13 12:12 System.map-7.0.0-14-generic
-rwxr-xr-x 1 root root 11001587 May 25 14:41 System.map-7.0.0-22-generic
-rwxr-xr-x 1 root root 308479 Apr 13 12:12 config-7.0.0-14-generic
-rwxr-xr-x 1 root root 308479 May 25 14:41 config-7.0.0-22-generic
drwxr-xr-x 5 root root 4096 May 31 21:59 grub
-rwxr-xr-x 1 root root 92774192 May 31 20:31 initrd.img-7.0.0-14-generic
-rwxr-xr-x 1 root root 156672 Nov 29 2025 mt86+ia32
-rwxr-xr-x 1 root root 161280 Nov 29 2025 mt86+x64
-rwxr-xr-x 1 root root 17275272 May 31 21:59 vmlinuz-7.0.0-14-generic
-rwxr-xr-x 1 root root 17275272 May 25 14:42 vmlinuz-7.0.0-22-generic

[die.boer]

xxx@xxx:~$ ls -l /boot
total 146760
-rwxr-xr-x 1 root root 11001551 Apr 13 12:12 System.map-7.0.0-14-generic
-rwxr-xr-x 1 root root 11001587 May 25 14:41 System.map-7.0.0-22-generic
-rwxr-xr-x 1 root root 308479 Apr 13 12:12 config-7.0.0-14-generic
-rwxr-xr-x 1 root root 308479 May 25 14:41 config-7.0.0-22-generic
drwxr-xr-x 5 root root 4096 May 31 21:59 grub
-rwxr-xr-x 1 root root 92774192 May 31 20:31 initrd.img-7.0.0-14-generic
-rwxr-xr-x 1 root root 156672 Nov 29 2025 mt86+ia32
-rwxr-xr-x 1 root root 161280 Nov 29 2025 mt86+x64
-rwxr-xr-x 1 root root 17275272 May 31 21:59 vmlinuz-7.0.0-14-generic
-rwxr-xr-x 1 root root 17275272 May 25 14:42 vmlinuz-7.0.0-22-generic

this is missing from /boot
initrd.img
initrd.img.old
vmlinuz
vmlinuz.old

those are symlinks that should look like this
vmlinuz -> vmlinuz-7.0.0-22-generic
initrd.img -> initrd.img-7.0.0-22-generic
something is preventing symlink creation in /boot, which is unusual for a normal ext4 filesystem.

we could carry on trying to fix this , but in my opinion if you are prepared to do a fresh install, that would probably be much easier
at the moment you have a kernel package failure AND ethernet issues, they might be related or 2 seperate problems created at the same time with an update...

[cherryForge]

xxx@xxx:~$ sudo modprobe -r alx && sudo modprobe alx && sleep 3 && sudo ethtool enp2s0
Settings for enp2s0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: Unknown!
Duplex: Unknown! (255)
Auto-negotiation: on
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
MDI-X: Unknown
Current message level: 0x0000xxxx (24804)
link ifup rx_err tx_err hw wol
Link detected: no

[die.boer]

xxx@xxx:~$ sudo modprobe -r alx && sudo modprobe alx && sleep 3 && sudo ethtool enp2s0
Settings for enp2s0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: Unknown!
Duplex: Unknown! (255)
Auto-negotiation: on
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
MDI-X: Unknown
Current message level: 0x0000xxxx (24804)
link ifup rx_err tx_err hw wol
Link detected: no

ok that rules out the simplest driver-initialization problem.

Reloading alx made no difference:

Link detected: no
Speed: Unknown!
Duplex: Unknown!

a fresh install is gonna be easier lol
before you go down that route , can you check that if you boot with kubuntu installer(live USB) , if ethernet works there ?
if it doesn't ,a reinstall is not going to fix it

[cherryForge]

this is the first time i tried with home on diffrent ssd partion, could that cause this problem?

i will try format,new partion and a fresh install when i have time. i will update you if it works better.

maybe i switch back to 24.04., i think that worked without problems.

and thank you for your help die.boer

edit: could it be the pc is to old for the step from 7.0.0.14 to 7.0.0.22? yes its getting a little old, but still fast enough for a lot of stuff

[oshunluvr]

this is missing from /boot
initrd.img
initrd.img.old
vmlinuz
vmlinuz.old

those are symlinks that should look like this
vmlinuz -> vmlinuz-7.0.0-22-generic
initrd.img -> initrd.img-7.0.0-22-generic
something is preventing symlink creation in /boot, which is unusual for a normal ext4 filesystem.

Those symlinks aren't necessary to boot and aren't used by GRUB as a default in a Kubuntu install. If one wishes them to be created, creating /etc/kernel-img.conf with these contents:

# Kernel Image management overrides
# See kernel-img.conf(5) for details
do_symlinks = yes
do_bootloader = no
do_initrd = yes
link_in_boot = yes
​

should do the trick. Not sure why this isn't included in Kubuntu as it is in Ubuntu. Also, I think the first two do_ lines are all that/s needed.

Regardless, I am confident this has nothing to do with the ethernet issue.

[oshunluvr]

I tested the above suggestion on a Kubuntu 26.04 VM installation and as expected the kernel symlinks are created. I only used the "do_symlinks = yes" and "do_bootloader = no" in the file.
do_bootloader = no

[oshunluvr]

So im running Linux 7.0.0-14-generic? Because of that there is no older Kernel to choose.
And somehow the unsucsesfull update messing with networkcard settings.

I believe you can install the 6.19.0-9-generic kernel. It's in the 26.04 repositories. You could also try installing the 7.0.0-22-generic kernel.

[die.boer]

could it be the pc is to old for the step from 7.0.0.14 to 7.0.0.22?

nope not at all
another suggestion ...after fresh install 1st check your ethernet is working reliably before upgrading
and then run

sudo apt update && sudo apt upgrade

(not full-upgrade) like before
also this

can you check that if you boot with kubuntu installer(live USB) , if ethernet works there ?
if it doesn't ,a reinstall is not going to fix it

[cherryForge]

oshunluvr the symlinks didn't work, comand not found. the first one i can install but no permission or something. i can post output tomorrow.

die.boer im pretty sure network and other basic stuff was working flawlessly from usb,
on first install until update
on second install until reboot the next day.
and i think it was restarting a few times during update. so i dont understand what changed.

checksum was ok but i will do a fresh download of the linux file too, just in case