Can't connect to local MySQL server through socket

Posted by Martin on Server Fault See other posts from Server Fault or by Martin
Published on 2010-05-19T12:39:23Z Indexed on 2010/05/19 13:32 UTC
Read the original article Hit count: 504

Filed under:

mysql

|

mysqld

I was trying to tune the performance of a running mysql-server by running this command:

mysqld_safe --key_buffer_size=64M --table_cache=256 --sort_buffer_size=4M --read_buffer_size=1M &

After this i'm unable to connect mysql from the server where mysql is running. I get this error:

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (111)

However, luckily i can still connect to mysql remotely. So all my webservers still have access to mysql and are running without any problems. Because of this though i don't want to try to restart the mysql server since that will probably mess everything up.

Now i know that mysqld_safe is starting the mysql-server, and since the mysql server was already running i guess it's some kind of problem with two mysql servers running and listening to the same port.

Is there some way to solve this problem without restarting the initial mysql server?

UPDATE: This is what ps xa | grep "mysql" says:

11672 ?        S      0:00 /bin/sh /usr/bin/mysqld_safe
11780 ?        Sl   175:04 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/run/mysqld/mysqld.sock --port=3306
11781 ?        S      0:00 logger -t mysqld -p daemon.error
12432 pts/0    R+     0:00 grep mysql

© Server Fault or respective owner

Can't connect to local MySQL server through socket

Posted by Martin on Stack Overflow See other posts from Stack Overflow or by Martin
Published on 2010-05-19T12:39:23Z Indexed on 2010/05/19 13:00 UTC
Read the original article Hit count: 504

Filed under:

mysql

|

mysqld

I was trying to tune the performance of a running mysql-server by running this command:

mysqld_safe --key_buffer_size=64M --table_cache=256 --sort_buffer_size=4M --read_buffer_size=1M &

After this i'm unable to connect mysql from the server where mysql is running. I get this error:

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (111)

However, luckily i can still connect to mysql remotely. So all my webservers still have access to mysql and are running without any problems. Because of this though i don't want to try to restart the mysql server since that will probably fuck everything up.

Now i know that mysqld_safe is starting the mysql-server, and since the mysql server was already running i guess it's some kind of problem with two mysql servers running and listening to the same port.

Is there some way to solve this problem without restarting the initial mysql server?

UPDATE: This is what ps xa | grep "mysql" says:

11672 ?        S      0:00 /bin/sh /usr/bin/mysqld_safe
11780 ?        Sl   175:04 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --user=mysql --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/run/mysqld/mysqld.sock --port=3306
11781 ?        S      0:00 logger -t mysqld -p daemon.error
12432 pts/0    R+     0:00 grep mysql

© Stack Overflow or respective owner

Related posts about mysql

How to remove MySQL completely with config and library files on ubuntu 12.04 gnome 3.0

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I tried everything till now: sudo apt-get remove mysql-server mysql-client mysql-common sudo apt-get purge mysql-server mysql-client mysql-common sudo apt-get autoremove and even more commands... But whenever I am trying to locate mysql. I get a no. of files related to mysql command: shell>>… >>> More
mysql: Cannot load from mysql.proc. The table is probably corrupted

as seen on Server Fault - Search for 'Server Fault'
Mysql was started: /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 but when I'm trying to do something: ERROR 1548 (HY000) at line 1: Cannot… >>> More
Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

as seen on Server Fault - Search for 'Server Fault'
A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL… >>> More
mysql: Bind on unix socket: Permission denied

as seen on Server Fault - Search for 'Server Fault'
Can't start mysql with: sudo /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 120222 13:40:48 mysqld_safe Starting mysqld daemon with databases… >>> More
MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

as seen on SQL Authority - Search for 'SQL Authority'
MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which… >>> More

Related posts about mysqld

No such file or directory - /var/run/mysqld/mysqld.sock

as seen on Server Fault - Search for 'Server Fault'
I tried to migrate a 5 year old ruby on rails application onto a new server with Ubuntu 8.04, Apache 2 and MySQL 5. The application failed to run. When I looked in the error logs, I noticed Errno::ENOENT (No such file or directory - /var/run/mysqld/mysqld.sock) I looked around my new server… >>> More
Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have mailserver configure using dovecot+postfix+mysql and it was runnig fine in the server(Ubuntu Server). But during last week it stopped working correctly. It doesn't send email. When I try to telnet localhost smtp I'm connecting successfully but when I do mail from:<[email protected]> and… >>> More
Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
My mysql installation was screwed up. I uninstalled and installed it multiple times. But I kept getting a hang or a error "cant connect". I now finally have it running with sudo -u mysql mysqld. How do I get mysqld to run at startup, and why do I need to run it as user mysql. Can I change it to run… >>> More
mysqld crashes on any statement

as seen on Server Fault - Search for 'Server Fault'
I restarted my slave to change configuration settings to skip reverse hostname lookup on connecting and to enable the slow query log. I edited /etc/my.cnf making only these changes, then restarted mysqld with /etc/init.d/mysql restart All appeared to be well but when I connect to msyqld remotely… >>> More
mysql weird connection problem

as seen on Server Fault - Search for 'Server Fault'
Hi guys! I've a weird problem. I've mysql 5.1 installed on my ubuntu 9.04. I've used it a long time (say 3 month) and everything was going right. Until i faced this really weird problem. When i want to connect to a random database i get this message: ERROR 2006 (HY000): MySQL server has gone away No… >>> More