Recently I discovered that my backups of my proxmox virtual machines were taking up too much space on my storage server. After doing some research, i found out that I could run fstrim -v / to remove deleted space from my drive.
Now what I needed was a way to automated it. Using Cron I was able to make it run every 30 min and generate a log file, to verify and make sure its working correctly. But after adding the cron entry, it was not running. I added the entry under
sudo crontab -e
Then added the folowering command at the end of the file:
*/30 * * * * fstrim -v / >> /home/user/trim.log
This would run fstrim on the selected volume / (root). But, since things are not as easy as that, it was recording an error:
fstrim: not found
After doing more research, I found out that sudo crontab -e would need the full path of the program. I went and made the following changes:
*/30 * * * * /sbin/fstrim -v / >> /home/user/trim.log
Now I have a log of fstrim then I added another line to the cron schedule
*/30 * * * * date >> /home/user/trim.log
Now i have a date time and result.