TS7700 The drawbacks - Revisited

One of my first posts was about some TS7700 drawbacks. Things have changed since then, so I find it not more than fair to give this an update. For those who are not that familiar with the virtualization engine, here's a graphical representation of its components :


Most of what I'm telling comes from the redbook 'IBM System Storage Virtualization Engine TS7700: Tape Virtualization for System z Servers'.

The first drawback - certainly also because of its price - was the large cache with a minimum of 6TB. You now have a choice starting at 2TB up to 6 TB with 1TB increments (p. 23). I guess it was also because of this difference with the B10 (with a maximum of 432GB) that an upgrade from a B10 VTS seemed a bit pointless. This upgrade is also possible now : "Outboard VTS migration provides an upgrade path for existing, standalone B10 or B20 VTS models to a standalone TS7700 Virtualization Engine through RPQ 8B3411" (p. 184).

The TS7700 still cannot connect to a 3494 tape library - for the time being. There's a Statement of Direction for "attachment of the TS7700 to the IBM TotalStorage 3494 Enterprise Tape Library to provide greater investment protection" (p. 5). Another SOD also mentions "utilization of the encryption capability of the TS1120 Tape Drive Model E05 by the TS77000" (p. 5).

A final drawback I mentioned was that the new 3952 drives (TS1120) could only run in 3952 J1A emulation mode, preventing the full use of larger tapes and the speed of the new TS1120 drives. This has now been lifted when you only use these new drives : "The TS7700 Virtualization Engine supports TS1120 Tape Drives and IBM 3592 Model J1A Tape Drives.(...) TS1120 drives assigned to a TS7700 run in J1A Emulation mode, when intermixed with J1A tape drives on the same TS7740, or in native E05 mode, when only E05 drives are attached to a TS7740" (p.29).