If you cannot restart your managed server (it enters a failed state) and you receive the following error, this may be due to excessive disk space usage on the database virtual machine (for example, the backup mount is at 75% for /u01).
Received exception while creating connection for pool "SOALocalTxDataSource": ORA-00257: Archiver error. Connect AS SYSDBA only until resolved.
This can result in archiving issues and the Oracle WebLogic Servers can only connect to the database as
To resolve this issue, increase the mount space. This enables the database to run again. If no issues are found in the archive logs, clean up the files occasionally to avoid similar issues in the future.