To Improve Communication Between Spectrum Protect Server (on Windows Platform) and VTL (Fujitsu Eternus CS)

1. There is no option to define control path failover for medium changer (or timeout value for this), so whenever there is VLP failover in VTL or even small connection break, TSM immediately reports Library is not accessible and if we have volumes in mounted/dismounting state it hangs and server needs to be rebooted. Moreover, On VTL also volumes remains in mounted state and have to be dismounted manually. So, there is no acknowledgement from either sides, it works in silos (kind of split brain situation). This sometimes also results in damaged backup object because TSM tries to read/locate the volumes from position which VTL says it is not available. So, there is high chance of data loss. 

2. Vjuk's works serially, so at a time only one volume can be restored from the backend (Physical Library) to VTL cache. So, a lot of manual work is Required for daily jobs like reclamation, restore, backups. We have to fetch the volumes manually from backend to cache to expedite the process. In other Backup software (CV) there is Prefetch feature which prefetch all the required volumes in cache (during backup, restore). So, either prefetch feature or solution for Vjuk's function to work in parallel to suffice the request (is needed for Windows Platform).

3. Currently we have only two library options for emulation (ADIC Scalar 1K and 10K) in the VTL. And IBM SP server only supports Scalar 10K with maximum lto4 drives (beyond LT04) is not supported. Also, the Windows native drivers does not work so we are using IBM SP driver for medium changer. And IBM tape device driver for Tape drives. Although it is emulation but more library options would be great.