The storage folder "Program Files\Dell\UCCS Analytics\Storage" is increasing in size.
In the cassandra.log you find the following error.
Increase the free space on the drive with the storage folder or move the storage folder to a drive with more free space.
Have a look at this KB to move the storage folder. https://support.quest.com/unified-communications-analytics/kb/146231
The free space on the drive with the storage folder needs to be greater than the size of the storage folder.