mysql randomly stopped working - mysql

hi my mysql was working i did nothing on it then today when i went to login to multicraft it gave me error 500 which means theres an issue with mysql and i tried to do $service mysql restart it didnt work so i did $service mysql status and i got this error
● mysql.service - LSB: Start and stop the mysql database server daemon
Loaded: loaded (/etc/init.d/mysql)
Active: failed (Result: exit-code) since Wed 2016-01-27 16:39:39 CET; 24min >ago
Process: 27320 ExecStop=/etc/init.d/mysql stop (code=exited, status=0/SUCCESS)
Process: 28147 ExecStart=/etc/init.d/mysql start (code=exited, >status=1/FAILURE)
Jan 27 16:39:39 ns3317389.ip-37-59-14.eu systemd[1]: Starting LSB: Start and >sto...
Jan 27 16:39:39 ns3317389.ip-37-59-14.eu mysql[28147]: /etc/init.d/mysql: >ERROR:...
Jan 27 16:39:39 ns3317389.ip-37-59-14.eu systemd[1]: mysql.service: control >proc...
Jan 27 16:39:39 ns3317389.ip-37-59-14.eu systemd[1]: Failed to start LSB: Start >...
Jan 27 16:39:39 ns3317389.ip-37-59-14.eu systemd[1]: Unit mysql.service entered >...
Hint: Some lines were ellipsized, use -l to show in full.

look in your /var/log/mysql/*.log logs
try to start mysql on the commandline
Example:
as root user: mysqld --console

Related

mysql does not restart

I've tried to restart mysql 5.7 :
service mysql restart
But it fails and i do not understand why :
Job for mariadb.service failed because the control process exited with error code.
See "systemctl status mariadb.service" and "journalctl -xe" for details.
And I dont see what's wrong in the logs :
systemctl status mariadb.service
● mariadb.service - MariaDB 10.1.37 database server
Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Mon 2019-02-25 22:02:52 GMT; 1min 9s ago
Docs: man:mysqld(8)
https://mariadb.com/kb/en/library/systemd/
Process: 15467 ExecStartPre=/usr/bin/install -m 755 -o mysql -g root -d /var/run/mysqld (code=exited, status=127)
Main PID: 28679 (code=exited, status=0/SUCCESS)
Feb 25 22:02:52 stretch systemd[1]: Starting MariaDB 10.1.37 database server...
Feb 25 22:02:52 stretch systemd[1]: mariadb.service: Control process exited, code=exited status=127
Feb 25 22:02:52 stretch systemd[1]: Failed to start MariaDB 10.1.37 database server.
Feb 25 22:02:52 stretch systemd[1]: mariadb.service: Unit entered failed state.
Feb 25 22:02:52 stretch systemd[1]: mariadb.service: Failed with result 'exit-code'.
Any help would be welcome...
I'm on Debian 9, with 1800Mo in ram free.
Here is what the journal says :
journalctl -xe
Feb 26 08:09:01 stretch CRON[16792]: pam_unix(cron:session): session opened for user root by (uid=0)
Feb 26 08:09:01 stretch CRON[16793]: (root) CMD ( [ -x /usr/lib/php/sessionclean ] && if [ ! -d /run/systemd/system ]; then /usr/lib/php/sessionclean; fi)
Feb 26 08:09:01 stretch CRON[16792]: pam_unix(cron:session): session closed for user root
Feb 26 08:17:01 stretch CRON[16794]: pam_unix(cron:session): session opened for user root by (uid=0)
Feb 26 08:17:01 stretch CRON[16795]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Feb 26 08:17:01 stretch CRON[16794]: pam_unix(cron:session): session closed for user root
Feb 26 08:25:23 stretch systemd[1]: Starting MariaDB 10.1.37 database server...
-- Subject: Unit mariadb.service has begun start-up
-- Defined-By: systemd
-- Support: https://www.debian.org/support
--
-- Unit mariadb.service has begun starting up.
Feb 26 08:25:23 stretch systemd[1]: mariadb.service: Control process exited, code=exited status=127
Feb 26 08:25:23 stretch systemd[1]: Failed to start MariaDB 10.1.37 database server.
-- Subject: Unit mariadb.service has failed
-- Defined-By: systemd
-- Support: https://www.debian.org/support
--
-- Unit mariadb.service has failed.
--
-- The result is failed.
Feb 26 08:25:23 stretch systemd[1]: mariadb.service: Unit entered failed state.
Feb 26 08:25:23 stretch systemd[1]: mariadb.service: Failed with result 'exit-code'.
I also got this error when upgrading to Debian Buster (from MariaDB 10.1 to 10.3). Running mysqld myself and mysql_upgrade both worked anyways. Try executing the following command to restart systemd on the fly. See also https://unix.stackexchange.com/a/419375.
systemctl daemon-reexec
If you don't do this, a reboot will probably fix this as well. Commenting out the ExecStartPre in /etc/systemd/system/mysql.service was not enough as the other ExecStartPre commands then failed instead (also with the exit code 127, i.e. "command not found").
Under Process: is the ExecStartPre returning with an error exist status
Based on error 127, I'd suspect that /usr/bin/install doesn't exist.

ERROR 2006 (HY000): MySQL server has gone away & conflict with max_allowed_packet

I wanted to import a sql dump
mysql -u username mydb < file.sql
And of course i get the classic ERROR 2006 (HY000) at line 1701: MySQL server has gone away message. No big deal i know that i need to increase the packet size. So i edit the /etc/mysql/mysql.cnf file and add the line max_allowed_packet=64M. But when i try to start the mysql server i get an error.
mysql.service - MySQL Community Server
Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Mon 2019-01-21 16:27:47 CET; 15s ago
Process: 9151 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid (code=exited, status=1/FAILURE)
Process: 9112 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
Main PID: 27620 (code=exited, status=0/SUCCESS)
Jan 21 16:27:47 aleksandar-pc systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Jan 21 16:27:47 aleksandar-pc systemd[1]: mysql.service: Scheduled restart job, restart counter is at 5.
Jan 21 16:27:47 aleksandar-pc systemd[1]: Stopped MySQL Community Server.
Jan 21 16:27:47 aleksandar-pc systemd[1]: mysql.service: Start request repeated too quickly.
Jan 21 16:27:47 aleksandar-pc systemd[1]: mysql.service: Failed with result 'exit-code'.
If i remove the code added for packets, the server can be started normally.
Can anyone help me with this, i really need to import this large db and don't know how to fix this mysql error.
Mysql verison: Ver 14.14 Distrib 5.7.25, for Linux (x86_64)
Linux: Ubuntu 18.04 LTS
Ok i forgot this [mysqld] above:
[mysqld]
max_allowed_packet=128M

MySQL general_log cannot be enabled. What am I doing wrong?

I'm on Ubuntu 18.04 with MySQL 5.7.24 and I'm trying to enable the general_log as described here.
So in my /etc/mysql/my.cnf I added this:
general_log = on
general_log_file=/tmp/mysql.log
I then stopped and started mysql again, but I get an error:
$ sudo service mysql stop
$ sudo service mysql start
Job for mysql.service failed because the control process exited with error code.
See "systemctl status mysql.service" and "journalctl -xe" for details.
So I checked out systemctl status mysql.service
● mysql.service - MySQL Community Server
Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Fri 2019-01-04 17:50:31 CET; 45s ago
Process: 27206 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/run/mysqld/mysqld.pid (code=exited, status=0/SUCCESS)
Process: 27613 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=1/FAILURE)
Main PID: 27208 (code=exited, status=0/SUCCESS)
Jan 04 17:50:31 librem systemd[1]: mysql.service: Failed with result 'exit-code'.
Jan 04 17:50:31 librem systemd[1]: Failed to start MySQL Community Server.
Jan 04 17:50:31 librem systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Jan 04 17:50:31 librem systemd[1]: mysql.service: Scheduled restart job, restart counter is at 5.
Jan 04 17:50:31 librem systemd[1]: Stopped MySQL Community Server.
Jan 04 17:50:31 librem systemd[1]: mysql.service: Start request repeated too quickly.
Jan 04 17:50:31 librem systemd[1]: mysql.service: Failed with result 'exit-code'.
Jan 04 17:50:31 librem systemd[1]: Failed to start MySQL Community Server.
In journalctl -xe I get pretty much the same.
I tried creating the log file in /tmp/mysql.log and chmodding it to 777, but after doing that, starting up mysql fails with the same errors.
Does anybody know what's wrong here?
In the end I solved it using this tip. Just copy pasting it here for future readers:
SET global log_output = 'FILE';
SET global general_log_file='/var/log/mysql/general.log';
SET global general_log = 1;
No need to restart. The user does need the SUPER privilege (GRANT SUPER ON *.* TO user1#localhost). This works for existing and new connections on the DB and is a global setting so it works for all databases.
It can be turned off with
SET global general_log = 0;

Webmin MySQL Error on starting

Firstly, I must say that I have not used these tools in the past so linux commands are not familiar to me.
Backstory:
On my Webmin server, I have been trying to get a Drupal Installation to work. I changed a parameter on the MySQL module and now the MySQL will not start.
Current Situation:
When I click "Start MySQL Server" I receive the follow:
Failed to start database : Redirecting to /bin/systemctl start
mariadb.service Job for mariadb.service failed because the control
process exited with error code. See "systemctl status mariadb.service"
and "journalctl -xe" for details.
I've search around this, and most people recommend to reinstall MariaDB.
I connected to the server with putty to get some more information
● mariadb.service - MariaDB database server
Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Tue 2017-08-01 16:29:00 UTC; 7min ago
Process: 22851 ExecStartPost=/usr/libexec/mariadb-wait-ready $MAINPID (code=exited, status=1/FAILURE)
Process: 22850 ExecStart=/usr/bin/mysqld_safe --basedir=/usr (code=exited, status=0/SUCCESS)
Process: 22823 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir %n (code=exited, status=0/SUCCESS)
Main PID: 22850 (code=exited, status=0/SUCCESS)
Aug 01 16:28:57 li172-89.members.linode.com systemd[1]: Starting MariaDB database server...
Aug 01 16:28:57 li172-89.members.linode.com mysqld_safe[22850]: 170801 16:28:57 mysqld_safe Logging to '/var/log/mariadb/mariadb.log'.
Aug 01 16:28:57 li172-89.members.linode.com mysqld_safe[22850]: 170801 16:28:57 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
Aug 01 16:29:00 li172-89.members.linode.com systemd[1]: mariadb.service: control process exited, code=exited status=1
Aug 01 16:29:00 li172-89.members.linode.com systemd[1]: Failed to start MariaDB database server.
Aug 01 16:29:00 li172-89.members.linode.com systemd[1]: Unit mariadb.service entered failed state.
Aug 01 16:29:00 li172-89.members.linode.com systemd[1]: mariadb.service failed.
[root#li172-89 ~]#
I gather that this means Mariadb wont even start so I should probably reinstall it. I did try to simply use a defaul my.cnf but that didn't really do anything.
Ideally, I do not want to lose any of the databases I have.
What should I do? Should I reinstall Mariadb? Is there a suitable guide that lists the commands? Could I install Mariadb but to another folder?
What is the best course of action at this point?

Mysql Error ERROR 2002 (HY000) persists after full reinstall

So I've been working on a rails server with MySQL and suddenly can't access my database. When I try to log in with mysql -u root -p I get ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2). I've read most of the forums I can find and looked through all the logs trying to reset mysqld.sock. I've tried reinstalling and repackaging unsuccessfully. The weird thing is that var/run/mysqld/ doesn't even exist after reinstalling.
So I decided to just back up my databases and overhaul everything. I cleaned out both apache and mysql with apt-get remove --purge and reinstalled. All went fine, apache launched fine, and then tried to relaunch mysql with systemctl start mysql which gave a prompt to check the log which says:
● mysql.service - MySQL Community Server
Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
Active: inactive (dead) (Result: exit-code) since Fri 2016-12-16 23:56:19 UTC; 17s ago
Process: 15690 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=1/FAILURE)
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: mysql.service: Control process exited, code=exited status=1
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: Failed to start MySQL Community Server.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: mysql.service: Unit entered failed state.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: mysql.service: Failed with result 'exit-code'.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: Stopped MySQL Community Server.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: mysql.service: Start request repeated too quickly.
Dec 16 23:56:19 ip-172-31-0-55 systemd[1]: Failed to start MySQL Community Server.
Update - I created the folder mysqld, which seems to allow sudo mysqld --initialize to run. Unfortunately this yielded the error
2016-12-17T00:16:36.298825Z 0 [ERROR] Can't change data directory owner to mysql
2016-12-17T00:16:36.299212Z 0 [ERROR] Aborting
So no party yet. Any thoughts would be hugely appreciated.
edit /etc/mysql/conf.d/mysql.cnf :
sudo nano /etc/mysql/conf.d/mysql.cnf
add this line :
socket=/var/run/mysqld/mysqld.sock
then restart mysql service :
sudo service mysql restart