Setting up mysql-server-5.7 (5.7.16-0ubuntu0.16.04.1) ...
Renaming removed key_buffer and myisam-recover options (if present)
Job for mysql.service failed because the control process exited with error code. See "systemctl status mysql.service" and "journalctl -xe" for details.
invoke-rc.d: initscript mysql, action "start" failed.
dpkg: error processing package mysql-server-5.7 (--configure):
subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of mysql-server:
mysql-server depends on mysql-server-5.7; however:
Package mysql-server-5.7 is not configured yet.
dpkg: error processing package mysql-server (--configure):
dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)
How to fix this