rman duplex

Currently we use rman to backup to tape. We are now going to write to disk.
Disk backupsets need to also go to tape as we can only retain so many days worth online.

We can use netbackup to take disk sets to tape or use duplex command to write to tape and disk for same backup.

Are any of you using duplex for similiar? Do both devices backup as fast as the device allows or does the speed of one impact the other?
Does this work well...any issues, etc?

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David


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