CDbConnection failed to open the DB connection after cache clear


I started to have issues with my Mailwizz. At some point, I was no longer able to even create and test a campaign. I would get Error 400 every time I would try to set up a campaign. Here's the screenshot of the error:

Then, I went to the backend to check the delivery logs and ran into another error, now 500 this time. Here's the screenshot:

I did some research and found here the suggestion to clear the cache. I went to var/www/mymailwizz/apps/common/runtime/cache and ran rm on all files. Then, I rebooted the server and after some time went to my mailwizz page only to find out that it's no longer working.

Then, I went to the server and enabled debugging in apps/init.php.

Upon my check, I've got a page with errors detailed in my followup reply in this thread.
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And, if this is of any help, here are the specifications of the server:

CPU: Intel Xeon E3-1270v6 - 4c/8t - 3.8GHz /4.2GHz
RAM: 32GB DDR4 ECC 2400 MHz
500 GB of storage space
Control Panel
Root access to the server
Access via the KVM/IP graphic console
Anti-DDoS Pro included

Here's current disk space on the server:



Found a fix on my own. The issue was that the space on the partition where mailwizz is placed was out of space.

Jai Bansal

New Member

My campaigns are giving error (Errcode: 28 "No space left on device")

I reduced Delivery servers logs removal days * from 180 to 60 days, in order to clear older logs.

But nothing happened in 1 hour. After how much time the CRON will run ? Else how to make it run manually ?