DEC RW500 StorageWorks Optical Disk Jukebox
This RW500 series Optical Jukebox contains one or more 5.25" magneto-optical drives that can use 650 MB or 1.3 GB WORM (write-once-read-many) or rewritable media. The drive can only access one side of the media at a time so the autochanger can remove the media from the drive and flip it over to the other side. The Hierarchical Storage Management (HSM) software was run under the OpenVMS operating system to manage the RW500. The HSM software could even keep track of disks that were removed from the RW500 and stored on a shelf.
We also have an Epoch Systems Model 60 Optical Disk Jukebox that looks identical to the DEC RW500.
The DEC announcement from May 31, 1993:
The StorageWorks RW500 Optical Library (Jukebox) family provides a range of solutions for automated access to large quantities of data—at costs lower than either on-line or operator-attended off-line storage. The RW500 family meets requirements for data-intensive applications and industries, including document image processing, CAD/CAM, CASE, COLD (Computer Output to Laser Disk), financial services, health care, technical publishing, and scientific data collection. Digital’s RW500 Optical Library family includes four models with formatted capacities ranging from 19 to 170 Gbyte. Multifunction drives support a mix of both rewritable and write-once (WORM) operations to maximize application design flexibility—subject to the functionality of the storage management software.
With Digital's Optical Storage Management Software (OSMS), the RW500 family can form a complete OpenVMS or Digital UNIX solution. OSMS provides transparent disk-like access to all platters within the jukebox. Functionally, the software makes each side of every platter in the jukebox appear as a logically mounted device to the applications, and mounts platters as those volumes are requested by the application. When a drive detects the presence of WORM or rewritable media, OSMS automatically invokes the appropriate file system (either Files-11 for Rewritable or the OSMSsupplied write-once file system) subject to the functionality of the particular operating system implementation of OSMS.
POLYCENTER Hierarchical Storage Management solution for Digital UNIX is an alternative storage management product which automatically stores files in the most effective media when considering the total cost of storage, frequency access, and latency to data. Active files are promoted to reside on magnetic disks for faster access times while infrequently used files revert to optical storage. Users and applications perceive a single integrated file system which may span magnetic disks and physical platters to offer a single logical volume thereby facilitating storage management and accessibility.
DEC RW500 Optical Disk Jukebox
Each of these units inside of the RW500 hold two WORM disks.
Epoch Systems Model 60 Optical Disk Jukebox