Thanks for the output, just reading the key elements:
Filesystem Size: 5TB
Total User-Visible Size: 4.75TB
Used Size: 4.75TB
Volume Size Used by Snapshot Copies: 4.71TB
You have correctly high-lighted the two snapsots which are consuming the most space:
hourly.2020-05-26_1005 3.21TB 64% 92%
hourly.2020-05-26_1105 555.3GB 11% 65%
There is a handy-command called "compute-reclaimable" which calculates the volume space that can be reclaimed (before actually deleting) if one or more specified Snapshot copies are deleted. However, it heavily uses system’s computational resources so it may reduce the performance for client requests and other system processes while it does the calculation.
::> volume snapshot compute-reclaimable -vserver ccb -volume ccb_CIFS_volume -snapshots hourly.2020-05-26_1005
If you delete those two snaps (which seems to be holding up the majority of the volume's space) you should be able to free up space.
Just on the side note - Does this volume have a replication partner (Vault) at another location, just in case if there is any particular file in that lot which might be needed, the other option in case you do not want to delete snaps then increase the space provided there is enough space on the aggregate.
Thanks!