Alain Raap

I found the cause of all our backup problems. After I made a change to the InnoDB settings of MariaDB (the buffer pool size was too small), the problem still existed yesterday. Yesterday I uninstalled the tool_excimer plugin, which I suspected that it could interfere the backups, because it was the only plugin that was active during the automated backup. This morning I checked the automated backup logs and all backups finished OK. It took me a week to find out the cause of our problems, fortunately all is running smoothly again.

Hi Richard,

How is your automated backup problem going, is it already solved? We have the same issue in our Moodle 4.1 environment, every night about 10% of the course backups fail in the automated backup process. I run this script outside Moodle in Linux cron and it starts at 22 hours and runs until the next morning. The backups that fail have status 800 and end with a dmlwriteexception. Debugging is impossible, I don't see the errors thrown by the database server (MariaDB).

See also my post here https://moodle.org/mod/forum/discuss.php?d=456577

I found the cause of all our backup problems. After I made a change to the InnoDB settings of MariaDB (the buffer pool size was too small), the problem still existed yesterday. Yesterday I uninstalled the tool_excimer plugin, which I suspected that it could interfere the backups, because it was the only plugin that was active during the automated backup. This morning I checked the automated backup logs and all backups finished OK. It took me a week to find out the cause of our problems, fortunately all is running smoothly again.

I already inspected that folder, the mdl_backup_controllers table showed the 54 failed backups
with status 800, in the backup logs the error I found there is dmlwriteexception, so it's a database
problem. To be continued..