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Shadow Tape feature managed from external software

The NearStore documentation (admin or cmdref) indicates that an imported cartridge from the Shadow Tape Pool is "immediately" visible in the VTL.

But how can be determined the new cartridge location in the nearStore VTL (which slot) at importation time ?

Does the shadow Tape use the EEP temporarily before being imported, and then, do the setting of the following options in the VTL:

"Select Enable EEP." "Select Automatically Move Physical Tapes from EEP to Slots" can solve this problem?

Many Thanks

Re: Shadow Tape feature managed from external software

These settings:

Enable EEP

Automatically Move Physical Tapes from EEP to Slots

are used for bringing physical tapes into the physical library. If a physical tape is put into the EEP port on the physical library, then the VTL will automatically move that physical tape to a slot within the physical library.

Similar behaviour can be acheived with a virtual library by using a configuration option within the virtual library. In the virtual library screen there is the "More Options" button. After pressing that you will see more options available for configuration. Check the setting:

Automatically move Tape from EEP to Slot

and make sure that it is enabled (the box is checked). Now if a virtual tape is put into the EEP of a virtual library the virtual library will automatically move the virtual tape to a slot within the virtual library. At this point the backup application should re-inventory the library (virtual library in this case) and the backup application would see the tape available for use.

Regarding Shadow Tape pool, using the Daily Tasks -> Virtual Tapes -> Import Virtual Tape from Shadow Pool will let you move a virtual tape from the Shadow Pool to a particular virtual library.

With NetBackup both the step of moving a virtual tape from Shadow Pool to a virtual library and the step of re-inventorying the library can be automated with our Shadow Tape Integration package that is available at: http://now.netapp.com/NOW/download/tools/nearstore_vtl_shadowtape_integration

Re: Shadow Tape feature managed from external software

Thanks for your response.

I am developping an application to perform automatic shadow tape import.

An essential point for me is to know if the tape goes through the EEP (in an invisible manner or not) or if it doesn't,

before coming into the VTL.

If not, is there a mean to know where it appears in the VTL by software (VTL commands or other).

Thanks

Re: Shadow Tape feature managed from external software

We need to be explicit, between physical and virtual, when talking about VTL components.

VTL = the actual physical controller

vlib = a virtual library on the VTL (there could be multiple vlibs on a VTL)

plib = the physical library attached to the VTL (there could be multiple plibs attached to a single VTL)

vtape = virtual tape

ptape = physical tape

EEP = entry/exit port... unfortunately this is ambiguous since there are EEPs on both vlib and plib

Shadow pool = a place where vtapes can reside (vtapes in the shadow pool are not in a vlib)

I'll explain the export process, which I think will then make explaining the import process easier, which will explain how the eep works.

A VERY simplified explanation of how the data flows....

Export process:

0. configure vlib with shadow pool

1. data is written to a vtape

2. the vtape is ejected from vlib by backup app

3. vtape data is copied to ptape

4. vtape is removed from vlib and put into shadow pool

Import process:

0. configure vlib with 'Automatically move Tape from EEP to Slot'

1. Daily Tasks -> Virtual Tapes -> Import Virtual Tape from Shadow Pool (this could be done via CLI)

2. From backup app, re-inventory vlib

Please let me know if you want a similar explanation for ptape and plib interaction with the VTL

Re: Shadow Tape feature managed from external software

At tape import, The EEP step is important for me as it gives the info to do the re-inventory.

So

if the "Automatically Move Tapes from EEP to Slots" option is

selected,

you confirm that the shadow tape moves though the EEP before appearing in

the VTL?

Re: Shadow Tape feature managed from external software

Entry (and ejects) of virtual Tapes into/out of virtual library goes through the mailslot on the virtual library.

Please post details of the software you are writing - this may be useful for other users...