package mysql-server-5.7 5.7.15-0ubuntu0.16.04.1 failed to install/upgrade: il sottoprocesso installato script di post-installation ha restituito lo stato di errore 1

[Christian Deligant]

.......ERROR: hook /usr/share/apport/general-hooks/ubuntu.py crashed:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport/report.py", line 197, in _run_hook
    symb['add_info'](report, ui)
  File "/usr/share/apport/general-hooks/ubuntu.py", line 66, in add_info
    check_attachment_for_errors(report, attachment)
  File "/usr/share/apport/general-hooks/ubuntu.py", line 171, in check_attachment_for_errors
    trim_dpkg_log(report)
  File "/usr/share/apport/general-hooks/ubuntu.py", line 469, in trim_dpkg_log
    report['DpkgTerminalLog'] = '\n'.join([str(line.decode('utf-8')) for line in lines])
  File "/usr/share/apport/general-hooks/ubuntu.py", line 469, in <listcomp>
    report['DpkgTerminalLog'] = '\n'.join([str(line.decode('utf-8')) for line in lines])
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe2 in position 10006: invalid continuation byte

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: mysql-server-5.7 5.7.15-0ubuntu0.16.04.1
ProcVersionSignature: Ubuntu 3.13.0-96.143-generic 3.13.11-ckt39
Uname: Linux 3.13.0-96-generic x86_64
.etc.apparmor.d.usr.sbin.mysqld: Error: [Errno 2] No such file or directory: '/etc/apparmor.d/usr.sbin.mysqld'
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
Date: Sun Oct 9 11:38:36 2016
ErrorMessage: il sottoprocesso installato script di post-installation ha restituito lo stato di errore 1
InstallationDate: Installed on 2013-03-22 (1297 days ago)
InstallationMedia: Ubuntu-Server 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120817.3)
Logs.var.log.daemon.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.conf.d.serverone.cnf:
 [mysqld]
 # Here you can see queries with especially long duration
 log_slow_queries = /var/log/mysql/mysql-slow.log
 long_query_time = 1
 #log-queries-not-using-indexes
MySQLConf.etc.mysql.mysql.conf.d.mysqld_safe_syslog.cnf:
 [mysqld_safe]
 syslog
MySQLVarLibDirListing: ['tm', 'mysql', 'mysql_upgrade_info', 'tellme', 'demade_2', 'zadig_todo', 'snlg_moodle', 'docebo', 'rca_learn', 'help3', 'Indirizzario', 'performance_schema', 'mantis', 'rca', 'ib_logfile1', 'formars', 'auto_lab', 'saepe_forum', 'saepe_mdl', 'Fadinmed', 'iss', 'demade_1', 'phplist', 'zadig_wiki', 'Help5', 'otrs2', 'Zadig_Russo_Web', 'saepe', 'ibdata1', 'ib_logfile0', 'privato', 'help3_mdl', 'intranet', 'moodle', 'iss_mdl', 'test', 'qdpm', 'clinev_ok', 'moodle_snlg', 'Bisanti', 'Zadig_Russo', 'demade_3', 'vascone', 'zadig_qualita', 'bacula', 'clinev', 'debian-5.5.flag']
ProcCmdline: BOOT_IMAGE=/vmlinuz-3.13.0-96-generic root=UUID=9cd5668c-6701-4af2-9596-25296d146fa7 ro nomdmonddf nomdmonisw nomdmonddf nomdmonisw nomdmonddf nomdmonisw nomdmonddf nomdmonisw nomdmonddf nomdmonisw nomdmonddf nomdmonisw
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: il sottoprocesso installato script di post-installation ha restituito lo stato di errore 1
UpgradeStatus: Upgraded to xenial on 2016-10-09 (0 days ago)
modified.conffile..etc.apparmor.d.usr.sbin.mysqld: [deleted]

[Robie Basak (racb)]

From log:

ERROR: Unable to start MySQL server:
2016-10-09T09:38:36.295087Z 0 [ERROR] unknown variable 'log_slow_queries=/var/log/mysql/mysql-slow.log'
2016-10-09T09:38:36.298246Z 0 [ERROR] Aborting
Please take a look at https://wiki.debian.org/Teams/MySQL/FAQ for tips on fixing common upgrade issues.
Once the problem is resolved, run apt-get --fix-broken install to retry.
dpkg: errore nell'elaborare il pacchetto mysql-server-5.7 (--configure):
 il sottoprocesso installato script di post-installation ha restituito lo stato di errore 1

[Christian Ehrhardt  (paelzer)]

From the log:
ERROR: Unable to start MySQL server:
2016-10-09T09:38:36.295087Z 0 [ERROR] unknown variable 'log_slow_queries=/var/log/mysql/mysql-slow.log'

This essentially is a diffferent but still same form of bug 1571865.
You will have to clean your config of no more supported configurations and it should start to work again.

[Christian Deligant (christian-deligant)]

I suggest to simply ignore the unknown variables and throw a warning instead of blocking mysql server to start... This "feature" broke beyond repair my OTRS installation that was happening during the same release upgrade... because the message complaining about upgrading did not give any hint that mysql server was stopped!
Result: more than 1 million tickets gone... I had to reinstall OTRS from scratch... but I still lost about 800 open tickets.
No blame, of course... but if mysql-server had just ignored the unsupported variable instead of dying it would have made my life a lot easier...