Job for mysql.service failed because the control process exited with error code Today I was working on my project which has the SQL and sending and receiving the information from flask to SQL and vice-versa, but all of the sudden without any change of the configuration it should me this error:


  ERROR 2003 (HY000): Can't connect to MySQL server on 'localhost'(111)


I tried to stop the service and work at the safe-mode but once I want to start again the service it gives me:


  Failed to start MySQL Community Server


I tried to swap the extra space but it did not work, I tried to remove the log but did not work, I tried to bind and unbind the 127.0.0.1 but it did not work.

I have attached my cnf below:

#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

[mysqld_safe]
socket      = /var/run/mysqld
nice        = 0

[mysqld]
#
# * Basic Settings
#
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
#skip-external-locking
#skip-grant-tables
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address       = 127.0.0.1
#
# * Fine Tuning
#
key_buffer_size     = 16M
#max_allowed_packet = 16M
thread_stack        = 192K
thread_cache_size       = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover-options  = BACKUP
#max_connections        = 100
#table_open_cache       = 64
#thread_concurrency     = 10
#
# * Query Cache Configuration
#
query_cache_limit   = 1M
query_cache_size        = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1
#
# Error log - should be very few entries.
#
log_error = /var/log/mysql/error.log
#
# Here you can see queries with especially long duration
#slow_query_log     = 1
#slow_query_log_file    = /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id      = 1
#log_bin            = /var/log/mysql/mysql-bin.log
expire_logs_days    = 10
max_binlog_size   = 100M
#binlog_do_db       = include_database_name
#binlog_ignore_db   = include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem


Edit

Here is the problem that error.log showed me : 

2020-03-17T10:32:14.514845Z 0 [ERROR] InnoDB: Unable to lock ./ibdata1 error: 11 
2020-03-17T10:32:14.514867Z 0 [Note] InnoDB: Check that you do not already have another mysqld process using the same InnoDB data or log files
I don't see anyone else answering this but I had the same issue and this could help someone.
The first error should be about network, binding by default an address such as 127.0.0.1 for localhost could trigger that and you should try to connect using the binding address a not 'localhost'.
Now, after entering safe mode I ran into a similar error! Even when the process of mysql is not &quot;Active&quot; there where still running processes after I stopped the safe-mode session and that was preventing the service to start. I was able to locate does processes using this command: sudo service mysql stop &amp;&amp; pkill -f mysql receiving this alert:
pkill: killing pid 8912 failed: Operation not permitted
pkill: killing pid 8913 failed: Operation not permitted
pkill: killing pid 9273 failed: Operation not permitted

after that I manually kill the processes using:
sudo kill 8912
sudo kill 8913
sudo kill 9273

and ran again the command: sudo service mysql stop &amp;&amp; pkill -f mysql
Finally I started the service again service mysql start and was running normally. I entered safe-mode to reset the password of the root user.