PFSense Crashs all night at araound 04:03

[admins]

Hi all
My PfSense Crashs all night at 4 a clock in the morning.
I've nothing seen in the crashlog, perhaps somebody could see what's the Problem:

The File is too large for this post. Crashlog:
https://kvg.mailcarrier.ch/owncloud/index.php/s/vxmzXvzFFklZEeS
Password: ~XBZTcg6

Thx
admins

[jimp]

That crash appears to be in ZFS disk i/o.

It could be a filesystem problem or it could be a disk/hardware issue