backing up recovery area in 10gR2...

Hi!
the doc says that rman always backs up the recovery area to an sbt channel. Is there any way to make a disk do the job of that sbt channel? I would like to use the recovery area on my server but for safety reasons there should be a backup on another machine. This is a relatively small installation and a real tape client is too expensive for us. We do however have one server that is backed up to tape and I can get space there (nfs, ftp upload, scp or similar things).

(10gR2, linux RH ES 4)

Lots of Greetings!
Volker

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