Virtualmin backups not working; problems dealing with MySQL dbs after updates

Hello, I have a very big problem, none of the backups (sometimes a manual one works) are being run without some problems. I have two scheduled for now, one that saves on the local machine and one via ssh to another server. Problem is in the last week all of a sudden none of my backups finishes succesfully. It seems that this is happening after some updates, perl included. I have only the default CentOS repos and Virtualmin. And epel but it’s not activated (used it once to install fail2ban). Even restarted the server.

This is not cool and can’t live without it. I did nothing to interfere in the settings that worked fine until now.

Everytime i get a different domain and different database that fails the backup, so it’s not specific, kind of random. This is an example with 3 different domains, 3 different database, 3 different applications:

Dumping MySQL database nameofthedb …
… dump failed! mysqldump: Couldn’t execute ‘SHOW TRIGGERS LIKE ‘jos_vm_manufacturer_category’’: Can’t read dir of ‘./nameofthedb/’ (errno: 24) (1018)

Dumping MySQL database nameofthedb ..
.. dump failed! mysqldump: Couldn't execute 'SHOW TRIGGERS LIKE 'tiki\_user\_taken\_quizzes'': Can't read dir of './nameofthedb/' (errno: 24) (1018)

Dumping MySQL database nameofthedb ..
.. dump failed! mysqldump: Couldn't execute 'SHOW TRIGGERS LIKE 'si\_biller'': Can't read dir of './nameofthedb/' (errno: 24) (1018)

The system is brand new - merely a month old: CentOS 6.4 Linux 2.6.32-358.2.1.el6.x86_64 on x86_64; Webmin version 1.620; Virtualmin version 3.99 Pro. And:

Perl version 5.010001
Path to Perl /usr/bin/perl BIND version 9.8.2
Postfix version 2.6.6 Mail injection command /usr/lib/sendmail -t
Apache version 2.2.15 5
PHP version 5.3.3 Webalizer version 2.21-02
Logrotate version 3.7.8 MySQL version 5.1.67
PostgreSQL version 8.4.13 ProFTPd version 1.33
SpamAssasssin version 3.3.1 ClamAV version 0.97.6

Howdy,

A MySQL “error 24” refers to a “too many files open” error.

You should be able to fix that by increasing the number of files MySQL is allowed to open.

There’s details on that here:

https://www.virtualmin.com/node/24829

It worked, waited a few days just to see if it is still happening. All fine now, thanks!