unknown variable 'query_cache_limit=1M'

[test051102]

This bug has been reported with earlier versions and is still present. Well, it's not the first time that mysql fails during upgrades...

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: mysql-server-8.0 8.0.25-0ubuntu0.20.04.1
ProcVersionSignature: Ubuntu 5.4.0-72.80-generic 5.4.101
Uname: Linux 5.4.0-72-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.17
Architecture: amd64
CasperMD5CheckResult: skip
Date: Fri May 14 08:40:31 2021
ErrorMessage: installed mysql-server-8.0 package post-installation script subprocess returned error exit status 1
InstallationDate: Installed on 2013-04-25 (2940 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
Logs.var.log.daemon.log:

MySQLConf.etc.mysql.conf.d.mysql.cnf: [mysql]
MySQLConf.etc.mysql.conf.d.mysqldump.cnf:
 [mysqldump]
 quick
 quote-names
 max_allowed_packet = 16M
MySQLVarLibDirListing: ['mysql', 'ASPNETDB', 'ibdata1', 'mysql.ibd', 'server-cert.pem', 'binlog.1503151', 'binlog.1503154', 'binlog.1503156', 'binlog.1503138', 'binlog.1503143', 'undo_002', 'ca-key.pem', 'client-cert.pem', 'binlog.1503140', 'sys', 'public_key.pem', 'binlog.1503130', 'binlog.1503150', 'binlog.1503135', 'binlog.1503136', 'binlog.1503152', 'binlog.1503139', 'private_key.pem', 'ib_logfile0', 'binlog.1503133', 'binlog.1503147', 'binlog.1503146', 'binlog.1503153', 'binlog.1503137', 'binlog.1503144', 'test', 'binlog.1503158', 'debian-5.5.flag', 'binlog.1503131', 'performance_schema', 'auto.cnf', 'binlog.1503155', '#innodb_temp', 'server-key.pem', 'binlog.1503145', '#ib_16384_0.dblwr', 'binlog.1503148', 'ib_buffer_pool', 'mysql_upgrade_info', 'ca.pem', 'binlog.1503157', 'binlog.1503132', 'binlog.index', 'debian-5.7.flag', '#ib_16384_1.dblwr', 'binlog.1503134', 'binlog.1503149', 'client-key.pem', 'undo_001', 'binlog.1503141', 'binlog.1503142', 'ib_logfile1']
ProcCmdline: BOOT_IMAGE=/boot/vmlinuz-5.4.0-72-generic root=UUID=61da1dc2-b1a3-4b51-bb76-073bd827539f ro quiet splash nomdmonddf nomdmonisw vt.handoff=7
Python3Details: /usr/bin/python3.8, Python 3.8.5, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.5
SourcePackage: mysql-8.0
Title: package mysql-server-8.0 8.0.25-0ubuntu0.20.04.1 failed to install/upgrade: installed mysql-server-8.0 package post-installation script subprocess returned error exit status 1
UpgradeStatus: Upgraded to focal on 2020-12-03 (161 days ago)

[Utkarsh Gupta (utkarsh)]

Hello,

Thanks for filing a bug.

> Well, it's not the first time that mysql fails during upgrades...

I am really sorry to see that. Though from the logs, I see:
[ERROR] [MY-000067] [Server] unknown variable 'query_cache_limit=1M'.

Query cache support was removed in 8.0 (ref https://dev.mysql.com/doc/refman/8.0/en/mysql-nutshell.html and https://mysqlserverteam.com/mysql-8-0-retiring-support-for-the-query-cache/).

Since these two options were in the 5.7 default config we do try to automatically handle it on upgrades, but the default config file location is /etc/mysql/mysql.conf.d/mysqld.cnf, so it only checks that location (/etc/mysql/my.cnf is also used by MariaDB, so by default it just includes the directory for the currently installed variant).

The fix for this should simply be to comment out the two lines with query_cache, but if you receive any similar errors after doing that you can check the mysql-nutshell page linked above to see if there's been any change for it.

[Utkarsh Gupta (utkarsh)]

Since this isn't really a bug, I am marking this as invalid. But should you feel otherwise, set it back to "New" with a reasoning and we'll take a look at it again. Thanks!