[CPANEL TIP] If you run out of space check this route first

[purplehead]

I got an “out of space” error and my site could not be opened.

The error screen said the server had no space left. When I checked in the console using:

df -h

the main disk still had space, which matched cPanel. But then I checked inode usage with:

df -ih

This showed the real issue: /tmp was at 100% inode usage. So the server was not out of normal disk space; it had run out of available file entries in the temporary filesystem.

MariaDB/MySQL was trying to create temporary SQL files in /tmp, but /tmp was a small separate/loop-mounted filesystem with too few inodes.

Fix:

I created a new MariaDB temp directory on the main disk:

mkdir -p /var/lib/mysqltmp
chown mysql:mysql /var/lib/mysqltmp
chmod 750 /var/lib/mysqltmp

This gave it the correct owner and restricted permissions:

drwxr-x--- 2 mysql mysql ... /var/lib/mysqltmp

Then I edited:

/etc/my.cnf

and added this under [mysqld]:

tmpdir=/var/lib/mysqltmp

Then I rebooted the server and checked it worked with:

mysql -e "SHOW VARIABLES LIKE 'tmpdir';"
df -ih /tmp

It worked! 15 minute panic over! 🙂