Unable to start MySQL server in Ubuntu - mysql

I run this command
service mysqld status
It show this
● mysqld.service
Loaded: not-found (Reason: No such file or directory)
Active: inactive (dead)
when i run this command to start sql server
sudo service mysql start
It show this
Failed to start mysql.service: Unit mysql.service not found.

I Found solution of this.
First i copy the database frm files for backup.
Then i removed sql server completely.
Then i install sql server again.
after that i copy the frm files and paste in /var/lib/mysql
run command sudo chown -R mysql:mysql /var/lib/mysql.
And last restart the sql server with sudo service mysql restart

Related

How to restore mysql database from `.ibd `files?

I upgraded my 18.04 to a 20.04 and I had a big crash on the Mysql update. Mysql was updated to 8.0 but with a failure. I was unable neither to start Mysql nor removing it.
So I dpkg forced uninstall MySql and backup /var/lib/mysql to a tar file.
To recover my data and perform a mysqldump, I tried to install MariaDB 10.3 and restore the MySQL database, but I couldn't restart the daemon.
From this, I created a whole new VM on Ubuntu 18.04:
apt update
apt install mysql-server
systemctl stop mysql
scp server:mysql.tar.gz .
tar xvzf mysql.tar.gz
chown -R mysql:mysql mysql
cp -r mysql/laravel /var/lib/mysql
systemctl start mysql
From mysql I can see my lavael schema, but it is empty. show tables; shows an empty set.
How can I restore this database?
Of course If I simply copy the backup to /var/lib/mysql I cannot start my daemon:
# systemctl start mysql
Job for mysql.service failed because the control process exited with error code.
See "systemctl status mysql.service" and "journalctl -xe" for details.

MySql/MariaDB cannot change default datadir on Debian 9.1 server

I have a problem to move the default datadir of Maria DB to another partition, it appears to be very common but i tried everything I can without luck.
Mysql is installed as Mariadb 10.1.26 with the default debian package (apt-get install mysql-server) on a Debian 9.1 (stretch) server, mysqld -v returns mysqld 10.1.26-MariaDB-0+deb9u1
Default_mysql_datadir : /var/lib/mysql
New_mysql_datadir : /home/mysql
/var/lib/mysql is mounted to "/" (/dev/md3)
/home/mysql is mounted to "/home" (/dev/md4)
What I've tried
# systemctl stop mysql
# mv /var/lib/mysql /home
Change datadir in /etc/mysql/my.cnf
# datadir = /home/mysql
Check if the rights/permissions are ok
# chown -R mysql.mysql /home/mysql
apparmor is NOT installed nor running on the system though the /etc/apparmor.d/usr.sbin.mysqld file is existing with the following rules :
/home/mysql/ r,
/home/mysql/** rwk,
I even tried to create and empty /var/lib/mysq folder refering to this bug
But when I start I always get the same error :
# systemctl start mysql
[Warning] Can't create test file /home/mysql/<user>.lower-test
#007/usr/sbin/mysqld: Can't change dir to '/home/mysql/' (Errcode: 13 "Permission denied") 2017-09-07 0:16:59 140119808397888 [ERROR] Aborting
mariadb.service: Main process exited, code=exited, status=1/FAILURE
Failed to start MariaDB database server.
mariadb.service: Unit entered failed state.
mariadb.service: Failed with result 'exit-code'.
Any suggestion ?
Thanks
Services started by Systemd have additional filesystem restrictions imposed by systemd.
It should be possible to provide values to systemd [Service] directives ProtectHome= and/or ProtectSystem= and/or ReadWritePaths= to resolve this issue.
I have similar problem:
When I start the mysql services a message is shown:
Job for mariadb.service failed because the control process exited with error code.
See "systemctl status mariadb.service" and "journalctl -xe" for details.
if I change the datadir from /etc/mysql/my.cnf again as default; np

mysql has stopped on my centos 6.5 server and failed to restart

I have tried to restart my mysqld on Centos server but gives me the below error :
170731 05:53:58 mysqld_safe Directory '/data/mysql' for UNIX socket file don't exists.
MySQL Daemon failed to start.
I have checked my mysql.sock file and is present where it should be and as defined in my.cnf
I have checked the permissions also and they are also perfect.
Any other reason its failing to restart ?
Looks like a permission error to me, try the following command.
chown -R mysql:mysql /data/mysql
This command makes the owner(group) of the folder /data/mysql to the user and group 'mysql'
After that the mysql-server should start again when running sudo service mysqld restart

Job for mysqld.service failed See "systemctl status mysqld.service"

Console says
[root#ip-172-31-18-2 mysql]# service mysqld start
Starting mysqld (via systemctl): Job for mysqld.service failed because the control process exited with an error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.
mysqld.service
[root#ip-172-31-18-2 mysql]# systemctl status mysqld.service
● mysqld.service - SYSV: MySQL database server.
Loaded: loaded (/etc/rc.d/init.d/mysqld)
Active: failed (Result: exit-code) since Sat 2017-02-18 20:59:17 IST; 36s ago
Docs: man:systemd-sysv-generator(8)
Process: 9925 ExecStart=/etc/rc.d/init.d/mysqld start (code=exited, status=1/FAILURE)
Feb 18 20:59:16 ip-172-31-18-2.ap-southeast-1.compute.internal systemd[1]: Starting SYSV: MySQL database server....
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal mysqld[9925]: MySQL Daemon failed to start.
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal mysqld[9925]: Starting mysqld: [FAILED]
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal systemd[1]: mysqld.service: control process exited, code=exited status=1
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal systemd[1]: Failed to start SYSV: MySQL database server..
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal systemd[1]: Unit mysqld.service entered failed state.
Feb 18 20:59:17 ip-172-31-18-2.ap-southeast-1.compute.internal systemd[1]: mysqld.service failed.
What I have tried until now:
mysqld_safe --defaults-file=/etc/my.cf
chown -R mysql:mysql /var/lib/mysql
/etc/init.d/mysqld start
/etc/init.d/mysqld stop
systemctl restart systemd-logind
rebooted the server
Still no luck.
my.cnf file
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.7/en/server-configuration-defaults.html
[mysqld]
#
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for a dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
#
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
#
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
This amazingly worked.
/etc/init.d/mysql stop
service mysql stop
killall -KILL mysql mysqld_safe mysqld
/etc/init.d/mysql start
service mysql start
I had the same error, the problem was because I no longer had disk space.
to check the space run this:
$ df -h
Then delete some files that you didn't need.
After this commands:
service mysql start
systemctl status mysql.service
mysql -u root -p
After entering with the root password verify that the mysql service was active
I met this problem today, and fix it with bellowed steps.
1, Check the log file /var/log/mysqld.log
tail -f /var/log/mysqld.log
2017-03-14T07:06:53.374603Z 0 [ERROR] /usr/sbin/mysqld: Can't create/write to file '/var/run/mysqld/mysqld.pid' (Errcode: 2 - No such file or directory)
2017-03-14T07:06:53.374614Z 0 [ERROR] Can't start server: can't create PID file: No such file or directory
The log says that there isn't a file or directory /var/run/mysqld/mysqld.pid
2, Create the directory /var/run/mysqld
mkdir -p /var/run/mysqld/
3, Start the mysqld again service mysqld start, but still fail, check the log again /var/log/mysqld.log
2017-03-14T07:14:22.967667Z 0 [ERROR] /usr/sbin/mysqld: Can't create/write to file '/var/run/mysqld/mysqld.pid' (Errcode: 13 - Permission denied)
2017-03-14T07:14:22.967678Z 0 [ERROR] Can't start server: can't create PID file: Permission denied
It saids permission denied.
4, Grant the permission to mysql
chown mysql.mysql /var/run/mysqld/
5, Restart the mysqld
# service mysqld restart
Restarting mysqld (via systemctl): [ OK ]
These are the steps I took to correct this:
Back up your my.cnf file in /etc/mysql and remove or rename it
sudo mv /etc/mysql/my.cnf /etc/mysql/my.cnf.bak
Remove the folder /etc/mysql/mysql.conf.d/ using
sudo rm -r /etc/mysql/mysql.conf.d/
Verify you don't have a my.cnf file stashed somewhere else (I did in my home dir!) or in /etc/alternatives/my.cnf use
sudo find / -name my.cnf
Now reinstall every thing
sudo apt purge mysql-server mysql-server-5.7 mysql-server-core-5.7
sudo apt install mysql-server
In case your syslog shows an error like "mysqld: Can't read dir of '/etc/mysql/conf.d/'" create a symbolic link:
sudo ln -s /etc/mysql/mysql.conf.d /etc/mysql/conf.d
Then the service should be able to start with sudo service mysql start.
I hope it work
In my particular case, the error was appearing due to missing /var/log/mysql with mysql-server package 5.7.21-1 on Debian-based Linux distro. Having ran strace and sudo /usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/mysqld.pid ( which is what the systemd service actually runs), it became apparent that the issue was due to this:
2019-01-01T09:09:22.102568Z 0 [ERROR] Could not open file '/var/log/mysql/error.log' for error logging: No such file or directory
I've recently removed contents of several directories in /var/log so it was no surprise. The solution was to create the directory and make it owned by mysql user as in
$ sudo mkdir /var/log/mysql
$ sudo chown -R mysql:mysql /var/log/mysql
Having done that I've happily logged in via sudo mysql -u root and greeted with the old and familiar mysql> prompt
if your problem not fix, you can try check more problem.
maybe mysql crash , like this :
you can check log in
sudo cat /var/log/mysql/error.log
or you check
sudo ls /var/crash
try
sudo chown mysql:mysql -R /var/lib/mysql
then start your mysql service
systemctl start mysqld
the issue is with the "/etc/mysql/my.cnf". this file must be modified by other libraries that you installed. this is how it originally should look like:
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License, version 2.0,
# as published by the Free Software Foundation.
#
# This program is also distributed with certain software (including
# but not limited to OpenSSL) that is licensed under separate terms,
# as designated in a particular file or component or in included license
# documentation. The authors of MySQL hereby grant you an additional
# permission to link the program and your derivative works with the
# separately licensed software that they have included with MySQL.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License, version 2.0, for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
#
# The MySQL Server configuration file.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html
# * IMPORTANT: Additional settings that can override those from this file!
# The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/
I was also facing same issue .
root#*******:/root >mysql -uroot -password
mysql: [Warning] Using a password on the command line interface can be
insecure. ERROR 2002 (HY000): Can't connect to local MySQL server
through socket '/var/lib/mysql/mysql.sock' (2)
I found ROOT FS was also full and then I killed below lock session .
root#**********:/var/lib/mysql >ls -ltr
total 0
-rw------- 1 mysql mysql 0 Sep 9 06:41 mysql.sock.lock
Finally Issue solved .
open my.cnf and copy the log-error path
then check the permission for the copied log file using
$ ls -l /var/log/mysql.log
if any log file permission may changed from mysql:mysql, please change the file permission to
$ chown -R mysql:mysql /var/log/mysql.log
then restart the mysql server
$ service mysql restart || systemctl restart mysqld
note: this kind of errors formed by the permission issues. all the mysql service start commands using the log file for writing the status of mysql. If the permission has been changed, the service can't be write anything into the log files. If it happens it will stopped to run the service
remove any command of "secure_file_priv" in /etc/mysql/my.cnf and restart mysql.
If you want to use a file in mysql, copy those files to the main folder.
The main folder is obtained this way : SHOW VARIABLES LIKE "secure_file_priv";
You can purge all mysql-related packages and reinstall them with the following commands:
PACKAGES="mysql-server mysql-community-server mysql-community-server-core mysql-client mysql-client mysql-community-client mysql-community-client-core mysql-common mysql-community-client-plugins php-mysql"
apt purge $PACKAGES
echo "any remaining installed packages:"
dpkg -l|grep ii|grep mysql
apt install --reinstall mysql-common
apt install $PACKAGES
If there are any remaining packages (apart from mysql-core), add those to your list
Backup your config or data and reinstall mysql
sudo apt remove --purge mysql-server
sudo apt purge mysql-server
sudo apt autoremove
sudo apt autoclean
sudo apt remove dbconfig-mysql
sudo apt-get remove --purge mysql* -y
sudo apt-get autoremove -y
sudo apt-get autoclean
Then install it again.
That works here.
i have got the same "systemctl status mysql.service" and "journalctl -xe" for details. ERROR.
after repeated deinstallation and installation does not work at all.
but this one work well> https://linuxtut.com/en/5a5b0f46620ae1b27b10/
you just need to remove everything from my.cnf file except [mysqld] and start the server. this really work. but you might not have the password for root in that case skip-grant-tables and restart server in safe mode and use mysql and
update mysql.user set authentication_string=null where user='root' and then can alter user 'root'#'localhost' identified by 'your_$$new_99pwd#';
then login to secure mode and then you can create new user.
Also don't forget to check on your docker containers, for me it was my docker has mysql running on the background.
Connect to the server using SSH.
Stop the affected MySQL service and the service plesk-web-socket to prevent it from attempting to start MySQL:
service mysql stop || service mariadb stop && service plesk-web-socket stop
Back up all the MySQL data storage files. By default, they are located in the directory /var/lib/mysql/.
For example:
cp -a /var/lib/mysql /root/mysql_backup
Add the parameter innodb_force_recovery to the section [mysqld] of the MySQL configuration file. This option allows starting MySQL service in the recovery mode and try creating dumps of databases.
For example:
vi /etc/my.cnf
[mysqld]
innodb_force_recovery = 2
Start the MySQL service.
after having tested several solutions without success, the one that finally worked is the following:
you can load the default configuration of your apache server
sudo a2ensite 000-default.conf
sudo a2dissite my.conf
systemctl reload apache2
then reload the configuration for your website
sudo a2ensite my.conf
sudo a2dissite 000-default.conf
systemctl reload apache2
I had the same issue and after hours the solution was for me:
Open this file nano /etc/mysql/my.cnf
#I use mysql service if you use mysqld service, type mysqld instead of mysql
[mysql]
innodb_force_recovery = 1
Had the same problem. Solved as given below.
Use command :
sudo tail -f /var/log/messages|grep -i mysql
to check if SELinux policy is causing the issue. If so, first check if SELinux policy is enabled using command #sestatus. If it shows enabled, then disable it.
To disable:
# vi /etc/sysconfig/selinux
change 'SELINUX=enforcing' to 'SELINUX=disabled'
restart linux
check with sestatus and it should show "disabled"
Uninstall and reinstall mysql. It should be working.

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock'

I have installed Centos7 update, removed MariaDB and done a fresh install of MySQL - additionally I have removed it and reinstalled it but everytime I connect to mysql -u root -p I get the titled error. Additionally I have looked at other tickets associated with this but still not making progress. If I run service mysqld restart it says "Redirecting to /bin/systemctl restart mysqld.service" and then just hangs. Really not a linux expert so not sure what is causing this?
I had the same problem and found out a few things after digging around. MariaDB is a drop-in replacement for mysql. On the new system, mysql is the MariaDB client (although I'm not clear on what that means). I checked to see if the service was running:
service mysqld status
which indicated:
Redirecting to /bin/systemctl status mysqld.service
mysqld.service
Loaded: not-found (Reason: No such file or directory)
Active: inactive (dead)
In other words, the mysqld service is not running.
Starting the service worked for me:
`systemctl start mariadb.service`
Now all the mysql commands work as expected.
To tie the last knot, enable the service at boot:
`systemctl enable mariadb.service`
Check the 'socket=' entry in your /etc/my.cnf within the [mysqld] section:
[mysqld1]
socket = /tmp/mysql.sock1
An alternate method is to provide the '-hhost' & '-Pport' parameters to the 'mysqladmin' or 'mysql' commands, to avoid using the socket.
mysql -u user -hservername -P3006 -p -Dschema
mysqladmin -u user -p -hhostname -Pport
Removing the dir fixed it - deleted the dir (with rm -rf "dir name") and then unintalled mysql "yum remove mysql mysql-server" then reinstalled "yum install mysql-server" and ran "service mysqld start"
If you have this problem with the start mysql service hanging - check the logs /var/log/mysqld.log as suggested by Jeremiah.
If you look into the MariaDB log file, you may see that the issue is related to creating pid file. To solve it: create the PID directory then change its owner to mysql:mysql