OpenVMS V6.0 through V8.3 support a maximum physical disk size of 1TB.  OpenVMS V8.4 introduced a maximum physical disk size of 2TB.  See Section 9.5 of the OpenVMS FAQ for more details: http://www.hoffmanlabs.com/vmsfaq/vmsfaq_013.html#file5

Caveats:

•Pre 7.2 version do not support a system disk larger than 32GB.

•Pre 7.2 version have a maximum of 1 million clusters, so for an n-GB drive the cluster size will be 2*n, which may get rather large.

•The SWXCR RAID controllers had their own hardware limitations.