I had an Ubuntu 24.04 LTS VM running on Apple Silicon, I upgraded it to 26.04 and every reboot I was unable to look for updates.
Modern Ubuntu releases transitioned repository definitions entirely to the deb822 format (/etc/apt/sources.list.d/ubuntu.sources), leaving /etc/apt/sources.list as a blank or commented stub.
I had to manually edit the /etc/apt/sources.list file and comment/remove any entries, then look for updates. This file was reverted back on every reboot. So the fix is applying the immutable attribute via
I'd expect a permanent fix, because locking this file may cause issues later on.
Modern Ubuntu releases transitioned repository definitions entirely to the deb822 format (/etc/apt/sources.list.d/ubuntu.sources), leaving /etc/apt/sources.list as a blank or commented stub.
I had to manually edit the /etc/apt/sources.list file and comment/remove any entries, then look for updates. This file was reverted back on every reboot. So the fix is applying the immutable attribute via
Code:
sudo chattr +i /etc/apt/sources.listI'd expect a permanent fix, because locking this file may cause issues later on.