NDMP & PTT

[jemmy2a]

All,

Need some advice about different between NDMP & Path To Tape?
What I know is both of it move the data via SAN directly to tape.

Thanks

[mph999]

I think you may be confused here ... NDMP backups (eg. backup the NDMP device) can go via lan or san, it depends where the drives are connected. If the drives are connected to the media server only, then the data is sent from the NDMP device to the media server. If the drives are connected to the NDMP device via the san, then the data is set directly to the drives over the SAN and does not go via the media server. Path to tape isn't used to make an initial backup, it is used to copy backup images that have been sent to an OST disk device. Path to tape would be over the san, but not all devices support this. I've only done it on a Quantum Dxi device configured as an OST disk storage unit, that was connected to another Quantum Dxi configured as a VTL. Path to tape is used to make a copy of a backup already residing on the disk storage, and again, is sent direct, not via a media server. So in summary ... NDMP backups relate to using NetBackup to backup the data on a NDMP device, either to tape or some other disk storage. Path to tape refers to making a copy of backup images, for example, that have been stored on OST disk, to another directly connected VTL. The OST disk is configured as a Storage Unit in NBU. The confusion I think arises because Path to tape uses the NDMP 'protocol' to work.

[Marianne]

Are you referring to Quantum DXi Path to Tape fuctionality?
This funtion is also know as NDMP DirectCopy.

See if this series of HOWTO docs help:

http://www.symantec.com/docs/HOWTO89213 
Configuring OpenStorage direct to tape 

Please also tell us more about your environment and configuration....

[jemmy2a]

Thanks for the reply.

For now I just want to know about ndmp & ptt solution, so there's no real environment.

So PTT and NDMP Direct Copy, from data flow is same right? Because its move direct from NDMP device to tape.
But when do NDMP Direct Copy, what is sent to the tape?
Is it the backup image or the real data that sent to the tape?

In above, you both mention PTT is from OST to VTL. But can PTT is configured from VTL to physical tape? Not just OST to VTL/physical tape.

Thanks