package mysql-common 5.7.12-0ubuntu1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2

[Chris]

got this error when trying to install mariadb-server-10.0. Have no other information than that.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: mysql-common 5.7.12-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
Date: Thu Jun 2 01:00:54 2016
Dependencies:

DuplicateSignature:
 package:mysql-common:5.7.12-0ubuntu1
 Setting up mysql-common (5.7.12-0ubuntu1) ...
 update-alternatives: error: alternative path /etc/mysql/my.cnf.fallback doesn't exist
 dpkg: error processing package mysql-common (--configure):
  subprocess installed post-installation script returned error exit status 2
ErrorMessage: subprocess installed post-installation script returned error exit status 2
InstallationDate: Installed on 2016-04-28 (35 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.1
 apt 1.2.12~ubuntu16.04.1
SourcePackage: mysql-5.7
Title: package mysql-common 5.7.12-0ubuntu1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2
UpgradeStatus: No upgrade log present (probably fresh install)
modified.conffile..etc.mysql.conf.d.mysql.cnf: [deleted]
modified.conffile..etc.mysql.conf.d.mysqldump.cnf: [deleted]
modified.conffile..etc.mysql.my.cnf.fallback: [deleted]

[Trebacz (david-trebacz)]

I understand that this bug exists, since I made some changes to my local file structure. In my case I deleted the file /etc/mysql/my.cnf.fallback while doing some troubleshooting/maintenance. I just copied the /etc/mysql/debian.cnf file and the script ran fine.

sudo /etc/mysql/debian.cnf /etc/mysql/my.cnf.fallback

 I assume the fallback is used if there is every a need.