Creating an ASM Disk Group with External Redundancy in Oracle

SQL Code

1create diskgroup data1
2external redundancy
3disk '/dev/raw/raw1'
4/

Or with multiple raw partitions

SQL Code

1create diskgroup data1
2external redundancy
3disk '/dev/raw/raw1'
4/

Or with multiple fail groups...

SQL Code

1create diskgroup data3
2normal redundancy
3failgroup controller1 disk '/dev/raw/raw4'
4failgroup controller2 disk '/dev/raw/raw6'
5/

Sample Oracle Output:

1
2no rows selected
3SQL>

Purpose:

• Establishes a new Automatic Storage Management (ASM) disk group named "data1" within the database.
• Employs external redundancy, indicating reliance on external mechanisms (like RAID) for data protection.
• Involves the disk "/dev/raw/raw1" as a member of the disk group.

Breakdown:

SQL

create diskgroup data1
external redundancy
disk '/dev/raw/raw1'
/

Key Points:

• create diskgroup data1: Initiates the creation of a disk group with the specified name.
• external redundancy: Designates the redundancy model, indicating that external mechanisms manage data protection.
• disk '/dev/raw/raw1': Lists the disk to be incorporated as a member of the disk group.
• /: Terminates the SQL statement for execution.

Insights and Explanations:

• ASM Structure: Disk groups serve as fundamental building blocks for storage management within ASM.

• Redundancy Options: ASM offers external redundancy (relying on external mechanisms) and normal/high redundancy (managing data protection internally).

• Disk Management: ASM simplifies storage administration by abstracting physical disks and providing a logical layer for managing database files.

• Additional Considerations:

  • Carefully plan disk group configuration based on redundancy needs and performance requirements.
  • Consider using multiple disks for improved performance and resilience.
  • Monitor disk group health and capacity proactively.

Overall, this SQL code demonstrates the process of establishing an ASM disk group with external redundancy, crucial for managing storage resources in Oracle databases.