Database Software

I have a 3.2TB database. The majority of the data resides in 18 partitioned tablespaces, 9 for data and 9 for index. The rest of the database is quite small, by comparison. Most of the data is input with no logging, but when in archivelog mode this database generates a huge amount of logs.

What we envision is to:

- put the database in archivelog mode, for the duration of the backup only.
- put the partitioned tablespaces in read-only mode
- export the data and index partitions as transportable tablespaces.
- copy the datafiles to a secondary disk location (takes about 15-20 hours)
- perform an incremental rman backup for the remaining database
- put the tablespaces back in read-write
- put the database in noarchivelog mode.

does this make sense? are there any serious flaws in the logic here?

all suggestions greatly appreciated.
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