Public bug reported: This is a report and also the fix. Please patch this so I don't have to any more.
Error: During run of automysqlbackup I get the following email: mysqldump: Got error: 1016: Can't open file: 'some_file.frm' (errno: 24 - Too many open files) when using LOCK TABLES mysqldump: Got error: 1016: Can't open file: 'some_file.frm' (errno: 24 - Too many open files) when using LOCK TABLES mysqldump: Couldn't execute 'show events': Out of resources when opening file './mysql/event.MYD' (Errcode: 24 - Too many open files) (23) Solution: There is an error in the maximum number of open files. The source is not in the kernel configuration! This solves this problem: Error: mysql: too much open files error Changing /lib/systemd/system/mysql.service and adding in the Service section 2 extra lines: [Service] ... ... ... LimitNOFILE=infinity LimitMEMLOCK=infinity After that: systemctl daemon-reload service mysql restart Problem goes away (at least until I run an apt update again :-) ) ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: mysql-server 5.7.22-0ubuntu0.16.04.1 ProcVersionSignature: Ubuntu 4.4.0-119.143-generic 4.4.114 Uname: Linux 4.4.0-119-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.18 Architecture: amd64 Date: Wed Jun 13 10:06:48 2018 InstallationDate: Installed on 2012-07-01 (2172 days ago) InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425) 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 MySQLConf.etc.mysql.mysql.conf.d.mysqld_safe_syslog.cnf: [mysqld_safe] syslog MySQLVarLibDirListing: False PackageArchitecture: all ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=nl_NL.UTF-8 SHELL=/bin/bash SourcePackage: mysql-5.7 UpgradeStatus: Upgraded to xenial on 2016-09-24 (627 days ago) ** Affects: mysql-5.7 (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apparmor apport-bug xenial -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1776615 Title: mysqldump: Got error: 1016: Can't open file: 'some_file' (errno: 24 - Too many open files) when using LOCK TABLES To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mysql-5.7/+bug/1776615/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs