Hello Victor! Just by a chance I noticed this email and wanted to add a comment.
04.10.2022 02:52, Viktor Dukhovni wrote: ..
Perhaps you previously had a "backports" package that uses a non-default release label, and it persisted across the upgrade... You may need to also look at the configs (IIRC) /etc/apt.d/ to see what release pins and preferences you have in place...
It is nearly impossible to have such a situation from a "backports" package on a debian-like system, unless whole packages database is seriously messed up. I can guess this is true for rpm-based setups too. Each package has a list of files recorded in the installed-packages database. The packaging system can not install two versions of the same package, it removes files from one version and installs files from the other version, - all old binaries are gone, and all new binaries are installed. There's a possibility to install a package with different name - something like postfix-test for example, - but only with different files, or else the two packages will conflict with each other. But it is not how backports work, when backporting, the package name is not changed. So it is either another postfix package name (highly unlikely, there's just no need for that), a messed-up package database (also very unlikely), or a manually installed postfix over the packaged version. But there's one other possibility remains still: when the upgrade process (installing new version of a package over old version) did not complete - regardless of backports or anything. dpkg (debian package manager) extracts files from the new version in _parallel_ with already existing files. This is in order for it to be able to rollback the installation if something goes wrong. So it is possible to have files from BOTH versions. And if the upgrade fails somewhere in this condition, the package will be marked as such, in a broken state - one have to tell dpkg to either repeat and complete the upgrade procedure, or to roll it back. dpkg -i shows the state of each package in the first column. "ii" there is for correctly installed. Everything else might need attention. Sometimes the upgrade fails, and people don't notice. Thanks, /mjt
Recovering a messed up system is an art. Good luck. If you can afford some down time, I'd attempt to save all user data and do a clean reinstall. The problem isn't the symlinks, it is multiple conflicting Postfix builds.
