Top 5 Timed Events - log file switch (archiving needed)

log file switch (archiving needed) -- Waiting for a log switch because the log that the LGWR will be switching into has not been archived yet. The main cause of this error is due to the non availability of space in the archive log destination.

Database is literally hung in this situation, even thought DB is not physically down, all the operations will come to a standstill affecting the uptime and availability of the system.

The best approach if one runs out of space in the archive log destination is to configure alternative location for archive log destination to avoid outages due to space issues.

Oracle has got an option to add Alternate attribute added to the log_archive_destination. Alternate archiving destination will be used if archiving to the original archiving destination fails. Below link will provide more information about the alternate option.

http://download.oracle.com/docs/cd/B10500_01/server.920/a96653/log_arch_dest_param.htm#77201