Chapter 7: Integrated Mirroring and Integrated Mirroring Enhanced

Following a hot swap event, the firmware readies the new physical disk by spinning it up and verifying that it has enough capacity for the mirrored volume. The firmware resynchronizes all hot-swapped disks that have been removed, even if the same disk is re-inserted. In a two-disk mirrored volume, the firmware marks the hot-swapped disk as the secondary disk and marks the other mirrored disk as the primary disk. The firmware resynchronizes all data from the primary disk onto the new secondary disk.

SMART Support

SMART is a technology that monitors hard disk drives for signs of future disk failure and generates an alert if such signs are detected. The firmware polls each physical disk in the volume at regular intervals. If the firmware detects a SMART ASC/ASCQ code on a physical disk in the IM/IME volume, it processes the SMART data and stores it in nonvolatile memory. The IM/IME volume does not support SMART directly, since it is just a logical representation of the physical disks in the volume.

Hot Spare Disk

One or two disk drives per controller can be configured as global hot spare disks, to protect data on the IM/IME volumes configured on the controller. If the firmware fails one of the mirrored disks, it automatically replaces the failed disk with a hot spare disk and then resynchronizes the mirrored data. The firmware is automatically notified when the failed disk has been replaced, and it then designates the failed disk as the new hot spare.

Media Verification

The firmware supports a background media verification feature that runs at regular intervals when the IM/IME volume is in optimal state. If the verification command fails for any reason, the other disk’s data for this segment is read and written to the failing disk in an attempt to refresh the data. The current Media Verification Logical Block Address is written to nonvolatile memory occasionally to allow media verification to continue approximately where it left off prior to a power-cycle.

Disk Write Caching

The firmware disables disk write caching by default for IM/IME volumes. This is done to increase data integrity, so that the disk write log stored in NVSRAM is always valid. If disk write caching were enabled (not recommended), the disk write log could be invalid.

NVSRAM Usage

The Integrated RAID firmware requires at least a 32K NVSRAM in order to perform write journaling. Write journaling is used to verify that the disks in the IM/IME volume are synchronized with each other.

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SUPER MICRO Computer AOCS2308LL8E Smart Support, Hot Spare Disk, Media Verification, Disk Write Caching, Nvsram Usage

AOCS2308LL8E specifications

Supermicro, a renowned leader in high-performance computing solutions, has introduced the AOC-S2308LL8E, a powerful SAS (Serial Attached SCSI) controller card designed to enhance storage performance and capability in enterprise systems. This cutting-edge controller provides exceptional functionality for organizations looking to handle large volumes of data efficiently.

The AOC-S2308LL8E features the LSI SAS2308 dual-core processor, which supports 12Gb/s data transfer rates, ensuring swift and reliable connections to storage devices. With its eight internal SAS/SATA ports, this controller card facilitates the connection of multiple drives, allowing for increased data throughput and redundancy, which are essential for critical applications such as database management and virtualization.

One of the standout characteristics of the AOC-S2308LL8E is its compatibility with both SAS and SATA drives. This flexibility allows organizations to choose between high-performance SAS drives or more economical SATA drives based on their specific storage requirements. The controller supports a wide array of RAID levels, including RAID 0, 1, 5, 6, 10, 50, and 60, providing users with the ability to select configurations that enhance data integrity and availability.

Additionally, the card is designed with an advanced cache memory that optimizes data access times, further enhancing overall performance. The AOC-S2308LL8E also features a low-profile form factor, making it suitable for various server chassis configurations, even in space-constrained environments.

In terms of connectivity, the AOC-S2308LL8E is equipped with dual mini-SAS connectors, enabling seamless connectivity to multiple storage devices. With support for a high number of simultaneous I/O operations, this controller card is well-suited for tasks requiring substantial bandwidth, like large-scale data processing and analytics.

Moreover, Supermicro's AOC-S2308LL8E comes with robust management and monitoring features, ensuring that users can maintain optimal performance levels while responding proactively to any potential issues. Built-in support for advanced error recovery techniques helps guarantee data integrity, a feature critical in any enterprise setting.

To summarize, the Supermicro AOC-S2308LL8E is an ideal solution for businesses looking to enhance their storage capabilities. With its combination of high data transfer rates, RAID support, compatibility with various storage drive types, and advanced management features, the AOC-S2308LL8E stands out as a reliable choice for maximizing performance in demanding environments. Organizations investing in this controller will benefit from its efficiency, reliability, and scalability, crucial for future-proofing their IT infrastructure.