ora_snp locks offline datafile

Hi all,
some days ago I created a big rollback_segment to refresh some huge snapshots; the rbs was created in a own separated filesystem which is laying on a own separated disk; operating system is AIX 4.3; the snaspshot was refreshed by a script which onlined the big rbs, refreshed the snapshot and offlined the big rbs. Today, since the snapshot finished successfully, I checked the big rbs which was (obviously) offline, dropped the big rbs and after issued a "drop tablespace RBS_TMP including contents". No error was showed.

After that I tryed to unmount the separated filesystem, but it's locked by three instances of ora_snp.

Does anybody have any suggestion for this issue?

Thanks,

Alessandro Vercelli

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