ZXnet

DEC StorageWorks Disk Canisters

The main purpose of StorageWorks disk shelves: to house disk canisters! Digital called these and the other devices that slot into StorageWorks Shelves (tape drives, protocol converters, RAID controllers, etc) StorageWorks Building Blocks (SBBs). The Shelves and the SBBs that go in them come in Narrow (N) and Wide (W) SCSI variants.

The canisters come in a number of colours. Green was the initial colour and most of these seem to be compatible with both Narrow and Wide SCSI shelves. Later they appeared to be coloured to match the servers and shelves they were going in. Grey presumably for Prioris and early AlphaServers, and later Top Gun Blue for later AlphaServers and later drive shelves. Apparently there were white ones too, presumably to match the frost white colour scheme later used by the PC division.

The LED on the left is the device activity indicator (green). The LED on the right is the fault indicator (amber) - if its on then the disk should be replaced. If the Fault LED is blinking it means the device is spinning down due to a fault.

The connector on the rear of a disk is only rated for 200 insertion and removal cycles, so its probably best not to go inserting and removing disks from shelves unnecessarily if you want to prolong the life of the shelf and disk canisters.

Label

Most disk canisters have a label on the front which give some basic specifications:

1. Order (part) number
2. Disk capacity
3. User assigned SCSI LUN (Logical Unit Number)
4. User assigned SCSI ID
5. User assigned Controller Channel Number
6. Device Bus Width - either Narrow (N) or Wide (W)
7. StorageWorks Shelf Compatibility
   • N — Narrow shelves only (like BA350)
   • W — Wide shelves only (like DS-BA356)
   • N/W — Either shelf type
8. Bus bit rate. The number is the bit rate in MBit/s. F indicates a fast device (10Mbps or faster), S indicates a slow device (5Mbps)
9. Transfer rate in MByte/s

Inventory

I've got quite a few of these, many of which haven't been used in quite a while so it's impossible to say how many of still work today.

The type column is device-bus-width/shelf-type. So W/W indicates a Wide SCSI drive compatible with Wide SCSI shelves only, while N/N-W indicates a Narrow SCSI drive compatible with either Narrow or Wide SCSI shelves.

The first number in the speed column is the transfer rate in MB/s, while the second number is the SCSI bus bit in MBit/s. For example, 40/F20 is 40MBytes/s with a Fast (F) bus speed of 20MBit/s.

Repacked Canisters

The following canisters have had their disks replaced and no longer match their label.

Documentation

• EK-SM2DR-UG — StorageWorks Building Block (SBB for Disk Drives - User's Guide