When originally built, the system had a screwed-up postfix installation;
in attempting to solve this problem, I wanted to uninstall postfix and
reinstall it. However, I don't think I should do that because the postfix
installation has an issue:
$ aptitude why postfix
i automysqlbackup Depends bsd-mailx | mailx
i A bsd-mailx Depends default-mta | mail-transport-agent
i A postfix Provides mail-transport-agent
Can anyone give me some clues on how to resolve this?
The main goal is to uninstall postfix and re-install it, without uninstalling
the automysqlbackup as this is a production system and the autobackup is
working properly. I believe the postfix dependency is for cases where the
auto-backup fails; it's also preventing mail from being delivered for failing
cron jobs.
sudo apt install --reinstall postfix
sudo dpkg-reconfigure postfix
might do what you want. In general, Debian derivatives will try
to prevent you from uninstalling critical machinery, like libc.