You can file this article under “not terribly useful but something I may refer to again in the future”. I’ve been migrating a bunch of data from one of my QNAP NAS devices at home to my OpenMediaVault NAS. Monit, my “faithful employee”, sent me an email to let me know I was filling up the filesystem on the OMV NAS.

By default OMV alerts at 80% full. You can change this though. Just jump on a terminal and run the following:

nano /etc/default/openmediavault

Add this line to the file

OMV_MONIT_SERVICE_FILESYSTEM_SPACEUSAGE=95

Then run the following commands to update the configuration

omv-mkconf collectd
monit restart collectd

Of course, you need to determine what level of filesystem usage you’re comfortable with. In this example, I’ve set it to 95% as it’s a fairly static environment. If, however, you’re capable of putting a lot of data on the device quickly, then 5% buffer may be insufficient. I’d also like to clarify that I’m not unhappy with QNAP, but the device I’m migrating off is 8 years old now and it would be a pain to have to recover if something went wrong. If you’re interested in reading more about Monit you can find documentation here.