WAVV
Requirement Form[Informati1]
Date: 08/29/2006 Requirement #: WAVV200705
Title: Provide emulated 34xx
devices delivered over SCSI tape drives
Detailed Problem Description: Complete the emulated device
over SCSI/FCP support introduced in z/VM 4.4 and 5.x to include emulation of
channel-attached tape to generic SCSI/FCP tape devices.
Priority:
High Requested Completion
Date: Next Release Requirement
Type: Compatibility/Migration
Business Justification: In many small to medium-sized shops, the amount of money
available to invest in mainframe technology is limited compared to the funding
accessible to the open systems environment. Often, significant tape resources
are duplicated or over-provisioned in the open systems environment, but are not
accessible for reuse in the mainframe environment due to the requirement for
specialized interfaces and separate management to support mainframe-specific
environments. Enabling software emulation of mainframe devices on top of a
generic SCSI/FCP infrastructure would allow System z infrastructure to leverage
these existing enterprise infrastructure investments directly, improving the
TCO argument for maintaining System z-based infrastructure. (It is clearly acknowledged that software
emulation has a performance impact compared to native performance)
Even given the recent price reductions for the System z BC and EC machines, in
some cases, the cost differential to implement separate tape for a System z
environment (or add specialized interfaces to support FICON attachment of an
existing tape library) is such that pricing is a deciding factor to preserve a
System z environment. Similarly,
environmental issues (floor space, power consumption, heat dissipation) may dictate
that additional tape units to support only a single platform argue against
retaining the System z solution as a "difficult to interoperate with"
solution.
With regard to tape, currently the largest supported FICON-attached tape unit
(pre-3592) supports a 40G uncompressed volume. Open systems tape units
regularly support 200G or greater volume sizes. With the dramatic increase in
data volumes, the inability of System z to access these commonplace devices
argues significantly against adoption of a System z based solution in place of
a Intel or other platform solution.
Tape emulation code for 3420 and 3480/90 tape over SCSI exists (developed for
the P390 and MP2k/3k), and offers direct support for all System z operating
systems currently supporting tape without additional development. Emulated tape
devices could easily be mapped to higher-capacity SCSI devices, providing
direct benefit for backup/DR and data exchange purposes.
There is also a security advantage in that encryption devices for SCSI devices
are substantially less expensive than replacing existing channel-attached
devices, and can participate in a enterprise-wide key management process that
does not need native OS support.
Impact: Further
argument to remove the mainframe and replace with "more compatible"
device.
[Informati1]Please be
precise and short.
The Benefit section
is extremely important – please make a business case.
Proofread - recheck accuracy of contact information before saving.
File as unique name-WRvviinn, where vv=vendor initials, ii=your initial, ‘nn’
to number each requirement. Ex.:
Wribwm01 ib=IBM, wm=wayne mery
Submit your labeled diskette (with your full name) to the requirements
coordinator, a black shirt WAVV manager, the registration desk or copy it to
the root drive of a registration or workroom PC.
*