One of the most critical events to monitor on an Oracle Database is your archive area. If the archive area fills up, your database will halt until it can continue to archive the redo logs. If your archive destination is set to a file system, then the Archive Area % Used metric is often the best way to go. This metric allows you to monitor a particular file system for the percentage space that has been used. However, there are a couple of things to be aware of for this critical metric.
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