ERROR! MySQL manager or server PID file could not be found! QNAP

Question

I am having an issue where MySQL isn\'t starting on my QNAP NAS.

I found this first by not being able to log in through phpMyAdmin - was getting error:

Answer 1

I know this is an older post, but I ran into the ERROR! MySQL server PID file could not be found! when trying to start MySQL after making an update to my.cnf file. I did the following to resolve the issue:

1. Deleted my experimental update to my.cnf

2. Deleted the .net.pid and .net.err files.

delete /usr/local/var/mysql/**<YourUserName>**-MBP.airstreamcomm.net.*

3. Ensured all MySQL processes are stopped.

ps -ax | grep mysql
kill **<process id>**

4. Started MySQL server as normal.

mysql.server start

Answer 2

First find PID of mysql service

ps aux | grep mysql

Then, you have to kill process

 sudo kill <pid>

After you again start mysql service

mysql.server start

Answer 3

Run the below commands and it will work.

Go to terminal and type

sudo chown -RL root:mysql /usr/local/mysql

sudo chown -RL mysql:mysql /usr/local/mysql/data

sudo /usr/local/mysql/support-files/mysql.server start

Answer 4

ERROR! MySQL server PID file could not be found!

This might be due to issues with disk space, disk inode usage or innodb corruption which may lead to the error.

The issue was with the pid file and the solution was:

1. SSH login to server as a root

2. Create directory /var/run/mysql

mkdir /var/run/mysql

3) Create a file with name as mysqld.pid

touch mysqld.pid

4. Change its ownership and group to mysql:mysql

   chown mysql:mysql mysqld.pid

5. Restart MySQL service

Done!

Answer 5

After a lot of searching, I was able to fix the "PID file cannot be found" issue on my machine. I'm on OS X 10.9.3 and installed mysql via Homebrew.

First, I found my PID file here:

/usr/local/var/mysql/{username}.pid

Next, I located my my.cnf file here:

/usr/local/Cellar/mysql/5.6.19/my.cnf

Finally, I added this line to the bottom of my.cnf:

pid-file = /usr/local/var/mysql/{username}.pid

Hopefully this works for someone else, and saves you a headache! Don't forget to replace {username} with your machine's name (jeffs-air-2 in my case).

Answer 6

Check if your server is full first, thats a common reason (can't create the PID file because you have no space). Run this to check your disk usage..

df -h

If you get something like this, you are full..

Filesystem      Size  Used Avail Use% Mounted on
/dev/vda1        40G   40G  6.3M 100% /

In that case, you need to start looking for what to delete to make room, or add an additional drive to your server.