RMAN backups to NFS OR FS 'snapshots'

For those who run backups to NFS

1. which device do you use.. with digiliant, and emc ax100, we haven't rearched much beyond 25megs per second (that's 9i, 10g with compression is faster)
2. have you ever had corruption problems? we recently had a corrupt lvl0, which I thought was difficult to 'achieve' over a tcp mounted nfs

We have also not used snapshots, but we might want to consider that.. Could someone describe the 'basics' with that? This is the way I think I understand it:
snapshots are taken at predetermined periods (db has to be in backup mode during each one?)
As snapshots get older, they are 'merged' But biggest quesion:
How does rman work with snapshots :) (e.g. what if we want to run rman duplicate, w/o impacting production)

We run EMC CX500's and CX300's, do those offer snapshot technology? How pricey :)

Any document links appreciated.

Thanks.
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We run Oracle 9iR2,10gR1/2 on RH4/RH3 and Solaris 10 (Sparc) remove NSPAM to email Received on Fri Mar 30 2007 - 12:49:02 CDT