What is RAID in ASM?

What is RAID in ASM?

RAID is an acronym for Redundant Array of Inexpensive (or Independent) Disks. RAID refers to a set of disks, called an array or a volume, that appears to the user as a single large disk drive. Depending on the configuration, this array provides improved reliability, response time, or storage capacity.

Which RAID is best for Oracle databases?

Oracle recommends “For best performance and reliability, choose a RAID device or a logical volume on more than one physical device and implement the stripe-and-mirror-everything (SAME) methodology.” when placing files on a filesystem. That reads as if oracle is recommending RAID 1+0.

What are the advantages of Oracle ASM?

ASM provides the following benefits: Striping—ASM spreads data evenly across all disks in a disk group to optimize performance and utilization. This even distribution of database files eliminates the need for regular monitoring and I/O performance tuning.

Which RAID level does not provide reliability?

Since RAID 0 provides no fault tolerance or redundancy, the failure of one drive will cause the entire array to fail; as a result of having data striped across all disks, the failure will result in total data loss. This configuration is typically implemented having speed as the intended goal.

What is a RAID 10 or RAID 1 0 array?

RAID 10, then, is a combination of levels 1 (mirroring) and 0 (striping), which is why it is also sometimes identified as RAID 1 + 0. Mirroring is writing data to two or more hard drive disks (HDDs) at the same time – if one disk fails, the mirror image preserves the data from the failed disk.

Which RAID mode is best?

RAID 10 is a combination of RAID 1 and 0 and is often denoted as RAID 1+0. It combines the mirroring of RAID 1 with the striping of RAID 0. It’s the RAID level that gives the best performance, but it is also costly, requiring twice as many disks as other RAID levels, for a minimum of four.

What is the best type of raid?

The best RAID for performance and redundancy

• The only downside of RAID 6 is that the extra parity slows down performance.
• RAID 60 is similar to RAID 50.
• RAID 60 arrays provide high data transfer speeds as well.
• For a balance of redundancy, disk drive usage and performance RAID 5 or RAID 50 are great options.

What is the difference between file system and ASM?

Use ASM for RAC: ASM provides a cluster file system manager. Use filesystems if you have disk-level mirroring and striping: Many disk arrays devices take care of striping and mirroring at the hardware level on your behalf.

When to use RAID 5 or ASM in Oracle?

As a result RAID 5 can be used to reduce costs without a significant impact on low performance systems. Automatic Storage Manager (ASM) is Oracle’s preferred solution to provide Stripe And Mirror Everything (SAME) storage. Even though ASM can provide double or triple mirroring, Oracle recommend hardware RAID is used in preference to ASM mirroring.

Which is better hardware RAID or ASM mirroring?

Even though ASM can provide double or triple mirroring, Oracle recommend hardware RAID is used in preference to ASM mirroring. As such, all LUNs presented to ASM are protected by hardware RAID, so ASM disk groups are defined using external redundancy and no failure groups.

How to minimize I / O contention between Oracle ASM disks?

Minimize I/O contention between Oracle ASM disks and other applications by dedicating disks in Oracle ASM disk groups. Choose a hardware RAID stripe size that is a power of 2 and less than or equal to the size of the Oracle ASM allocation unit. For Linux, use the Oracle ASMLib feature to provide consistent device naming and permission persistency.

Which is the best RAID system for Oracle?

Each disk is mirrored individually and striping occurs across all the mirrored pairs. This is the best RAID for Oracle. This RAID level stripes data and parity information across 3 or more disks.