I did not properly track hard drive space. While copying some files over to the DNS-345 the storage limit was met and an error message appeared "...no space...". As a result, the DNS-345 disappeared from the network. Similarly, the web UI was accessed to see if the problem could be resolved, however, none of the folder structure (or files) appears.
The DNS-345 contains four 3Tb SATA drives formatted to RAID 5.
Through diagnostics, all four drives appear to be good.
Is it possible to access the RAID 5 drives to "free up some space" and resume accessing the drive normally?