package:mysql-server-5.7:5.7.25-0ubuntu0.16.04.2 Installing new version of config file /etc/mysql/debian-start ... Renaming removed key_buffer and myisam-recover options (if present) ERROR: Unable to start MySQL server: 2019-04-17T13:53:44.023715Z 0 [ERROR] unknown variable 'table_cache=4000' 2019-04-17T13:53:44.028750Z 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: error processing package mysql-server-5.7 (--configure): subprocess installed post-installation script returned error exit status 1