Hi,
Thanks for the log.
It appears that the ST4000LM024 disk partitions are being skipped
Jun 09 21:09:43 volumio-rp4-lan volumio[699]: info: Ignoring mount for partition: boot
Jun 09 21:09:43 volumio-rp4-lan volumio[699]: info: Ignoring mount for partition: volumio
Jun 09 21:09:43 volumio-rp4-lan volumio[699]: info: Ignoring mount for partition: volumio_data
Jun 09 21:09:43 volumio-rp4-lan volumio[699]: info: Ignoring mount for partition: 4TB_SMR
This can only mean that the disk is not being reported by the OS as a removable USB device. We can try to find out why this is, see below.
The check is new for Volumio 3, due to the fact that removable disks are being handled slightly different because of Debian Buster.
Reading any internal disk in the system is causing seriously performance issues (with a deadlock in some situations) with x86 installations, so this was temporarily blocked by only allowing usb disks.
It will be replaced by a future option for the user to select the disk(s) to be read, similar to the way a network share can be selected.
Could you show us the result of
lsblk -o RM,HOTPLUG
It may give us a clue why the disk is not reported as removable device.