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ASM Mirroring

Redundancy Level The type of a ASM disk group is based on three redundancy levels: Normal ASM provides two-way mirroring by default. A loss of one ASM disk is tolerated. Use can optionally choose three-way or unprotected mirroring for a file in a NORMAL redundancy disk group. A file specified with HIGH redundancy (three-way mirroring) … Continue reading


This is for 11gR2. The length of DB_NAME is limited to 8 characters; DB_UNIQUE_NAME is limited to 30 characters. DB_UNIQUE_NAMEĀ  can contain alphanumeric, underscore (_), dollar ($), and pound (#) characters, but must begin with an alphabetic character. INSTANCE_NAME defaults to ORACLE_SID. Oracle document does not specify the limit for INSTANCE_NAME length. However if you … Continue reading