package mysql-server-5.7 5.7.15-0ubuntu0.16.04.1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[Helge Doering]

Probably relates to LP: #1612517

Looks like mysql is not able to upgrade from 5.5 to 5.7 (trusty to xenial).
I'm not sure from which version the config originates. After the option to send this report, I also saw this message in the terminal:

Setting up mysql-server-5.7 (5.7.15-0ubuntu0.16.04.1) ...
Renaming removed key_buffer and myisam-recover options (if present)
ERROR: Unable to start MySQL server:
2016-10-18T16:07:35.642062Z 0 [ERROR] unknown variable 'table_cache=256'
2016-10-18T16:07:35.648308Z 0 [ERROR] Aborting

After removing the opposing statement from /etc/mysql/my.cnf (and starting apt-get -f install) the upgrade continued successfully (DB and tables upgraded and DB started) and the server restarted OK.
JFYI

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: mysql-server-5.7 5.7.15-0ubuntu0.16.04.1
ProcVersionSignature: Ubuntu 3.13.0-98.145-generic 3.13.11-ckt39
Uname: Linux 3.13.0-98-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
Date: Tue Oct 18 15:54:05 2016
ErrorMessage: subprocess installed post-installation script returned error exit status 1
Logs.var.log.daemon.log:

Logs.var.log.mysql.error.log:
MySQLConf.etc.mysql.conf.d.mysql.cnf: [mysql]
MySQLConf.etc.mysql.conf.d.mysqld_safe_syslog.cnf:
 [mysqld_safe]
 syslog
MySQLConf.etc.mysql.conf.d.mysqldump.cnf:
 [mysqldump]
 quick
 quote-names
 max_allowed_packet = 16M
MySQLConf.etc.mysql.mysql.conf.d.mysqld_safe_syslog.cnf:
 [mysqld_safe]
 syslog
MySQLVarLibDirListing: ['ibdata1', 'backup', 'mysql', 'ib_logfile0', 'phpmyadmin', 'mysql_upgrade_info', 'piwik', 'performance_schema', 'ib_logfile1', 'debian-5.5.flag', 'zabbix']
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-3.13.0-98-generic root=UUID=4debcc35-8617-4fdb-a912-19421d092134 ro text
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.1
 apt 1.2.12~ubuntu16.04.1
SourcePackage: mysql-5.7
Title: package mysql-server-5.7 5.7.15-0ubuntu0.16.04.1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to xenial on 2016-10-18 (0 days ago)

[Joshua Powers (powersj)]

Thank you for taking the time to report this bug and helping to make Ubuntu better.

> After removing the opposing statement from /etc/mysql/my.cnf
> (and starting apt-get -f install) the upgrade continued
> successfully (DB and tables upgraded and DB started) and the
> server restarted OK.

Awesome! As you discovered mysql's variable/settings/configuration names have changed over the years and upgrading from 5.5 to 5.7 exposed that. The fix is exactly as you describe, needing to update your configuration.

> JFYI

Thanks!

[Launchpad Janitor (janitor)]

[Expired for mysql-5.7 (Ubuntu) because there has been no activity for 60 days.]