How to Fix an (errno: 24) in MySQL

Upon checking the mysql logs in /var/lib/mysql/HOSTNAME.err, I got error as :

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[ERROR] /usr/sbin/mysqld: Can't open file: './database/table.frm' (errno: 24)
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errno: 24 simply means that too many files are open for the given process. There is a read-only mysql variable called open_files_limit that will show how many open files are allowed by the mysqld.

A lot systems set this to something very low, like 1024. When creating a large number of partitions or tables, MySQL may mysteriously stop working and will generate this eeror.

Add the following parameter in /etc/my.cnf file and restart mysql service.

[mysqld]
open_files_limit = 100000