Virtualmin just runs the “mysqldump” command and returns the output it produced.
It’s possible what’s happening is that the exact command being used is different, so when you ran it on the command line, it didn’t trigger the problem that was produced during the backups.
What distro/version is it that you’re using?
And was the MySQL version upgraded recently?
Lastly, what is the output of this command:
mysql -V
The issue you’re seeing can sometimes occur when upgrading to certain MySQL versions.
mysql -V returns: mysql Ver 14.14 Distrib 5.5.43, for Linux (x86_64) using readline 5.1
Linux distro is: CentOS 6.6 (64bits)
I upgraded mysql to the above version during server initial setup. However, I never tried to do Virtual Server Backup since (roughly 2 weeks ago).
In /etc/webmin/mysql/config I have: login=root
I would like to mention that I have few virtual servers on this system and the Virtual Server Backup goes through fine for 2 servers and then hits the error on the 3rd one which happens to be a Wordpress website. If I exclude it, the backup will continue and stops again at the next Wordpress site. I don’t believe this common denominator is the culprit but I figured I’d mention it.
Thanks Eric! Now that I dug deeper in my rusty memory, those 2 Wordpress sites were migrated in right before I upgraded MySQL. The solution provided in the link you mentioned makes perfect sense in my case.