When upgrading packages in Debian, often when files were edited, the package manager creates extra files as in:
/etc/default/grub.dpkg-dist
/etc/mysql/my.cnf.dpkg-dist
More rarely, those files can create problems when upgrading production servers.
I do not feel that is a particular good solution deleting them by hand or using scripts. Is there any dpkg configuration where their creation can be forbidden?
No, I don't think that there is such an option for dpkg. There are several --force-conf* options that can change the behaviour of dpkg regarding configuration file conflicts. See this question and in this article.
But with any option, when there is a config file conflict, it will either
.dpkg-dist, or.dpkg-old You could write a post install script to get rid of those files, but I don't think that would be a good idea. When there is a conflict, it is worth looking into what changed.
The files with .dpkg-* suffix should not cause any problems. I would assume the problems rather come from changes in the way the new package version interprets the old config file.
