Introduction

This article describes how you can set up a Broadcom MegaRAID SAS 9361-8i controller card and also describes its key features, based on which you can decide what configuration is best suited for your environment. Here, you can get an overview of the different backplanes that are used in OpenPOWER systems.

Overview of the MegaRAID-SAS 9361-8i controller card

Some of IBM OpenPOWER systems, both IBM POWER8® and IBM POWER9™ support MegaRAID-SAS 9361-8i controller cards. This article describes how to configure the card and outlines some of the main features of this controller card. Figure 1 illustrates the MegaRAID-SAS 9361-8i controller card. In the name, the letter i stands for internal. What this means is that you can connect this adapter to the internal backplane of a server. There are two types of backplanes for the OpenPOWER systems, with 12 disk bays. The difference between the two is that one backplane can support up to four NVMe disks and the other cannot support these disks. Figure 2 shows a typical backplane.

Functional verification tests for the Broadcom MegaRAID SAS 9361-8i controller card are automated and is open source. Anyone can add new functional verification tests to the repository and this helps the community at large.

Link to the repository: https://github.com/avocado-framework-tests/avocado-misc-tests/tree/master/io/disk/Avago_storage_adapter

Figure 1. MegaRAID SAS 9361-8i
alt

Figure 2. Backplane
alt

Key advantages of the MegaRAID-SAS 9361-8i controller card

A MegaRAID-SAS 9361-8i controller card:

  • Accelerates performance through 12 Gbps solutions for next-generation data centers, web, and cloud
  • Delivers enterprise-class data protection and security
  • Preserves investment in 6 Gbps and 3 Gbps drives
  • Supports advanced software options
  • Connects up to 128 3 Gbps, 6 Gbps, or 12 Gbps SATA and SAS devices

Overview of RAID levels

This section provides an overview of the different Redundant Array of Independent Disks (RAID) levels. The MegaRAID-SAS 9361-8i controller card supports various RAID arrays. A few basic RAID arrays are described here.

RAID 0 (striping)

RAID 0, also known as disk striping, is a technique that breaks up a file and spreads the data across all the disk drives in a RAID group. The benefit of RAID 0 is improved performance. RAID 0 is ideal for noncritical storage of data that has to be read or written at a high speed.

RAID 1 (mirroring)

Disk mirroring, also known as RAID 1, is the replication of data to two or more disks. Disk mirroring is a good choice for applications that require high performance and high availability, such as transactional applications, email, and operating systems. RAID 1 is ideal for mission-critical storage, such as for accounting systems. It is also suitable for small servers in which only two data drives are used.

RAID 5 (striping with parity)

RAID 5 is a RAID configuration that uses disk striping with parity. As data and parity are striped across all the disks, no single disk is a bottleneck. Striping also allows you to reconstruct data during disk failure. Read and write operations are more evenly balanced in this configuration, making RAID 5 the most commonly used RAID method. RAID 5 is a good all-round system that combines efficient storage with excellent security and decent performance. It is ideal for file and application servers that have a limited number of data drives.

RAID 6 (striping with double parity)

RAID 6, also known as double-parity RAID, uses two parity stripes on each disk. It allows two disk failures within the RAID set before any data is lost. RAID 6 is a good all-round system that combines efficient storage with excellent security and decent performance. It is preferable over RAID 5 in file and application servers that use many large drives for data storage.

Configuring RAID levels by using the MegaRAID SAS 9361-8i controller card

You can manage the MegaRAID SAS 9361-8i controller card by using StorCLI, which is a CLI tool. You can download this tool from the MegaRAID SAS 9361-8i website. Install rpm using the following command:

rpm -ivh storcli64-007.0305.0000.0000-2.ppc64le.rpm

Once installed, you will see the tool in /opt/MegaRAID/storcli. This tool is a binary file that you can run from any location. Before running the tool set executable permission for the tool using the following command:

chmod u+x storcli64

After you run this command, you can use the tool. The following are the basic commands from which you can run different operations on the adapter.

Creating a RAID array

Run the following command:

# ./storcli64 /c0 add vd r0 drive=18:6

Where:

  • c0 is the controller ID
  • r0 is Raid 0
  • drive=18:6 indicates that the enclosure ID is 18 and the slot ID is 6

Refer to the following (example) output:


Controller = 0

Status = Success

Description = Add VD Succeeded

Adding a global hot spare

Run the following command:

/root/storcli64 /c0/e8/s3 add hotsparedrive

Refer to the following (example) output:


Controller = 0

Status = Success

Description = Add Hot Spare Succeeded.

Starting the rebuild operation and monitoring the progress

Run the following command:

/root/storcli64 /c0/e8/s6 start rebuild

Output similar to the following is displayed:


Status = Success

Description = Start Drive Rebuild Succeeded.

Run the following command:

/root/storcli64 /c0/e8/s6 show rebuild

Output similar to the following is displayed:


Controller = 0

Status = Success

Description = Show Drive Rebuild Status Succeeded.



------------------------------------------------------------------

Drive-ID     Progress%   Status      Estimated Time Left

------------------------------------------------------------------

/c0/e8/s6 7 In progress 3 Minutes(newline)

Similarly, you can perform other operations. Run the following command to view information about the supported operations on this controller card.

/root/storcli64 help

The MegaRAID SAS 9361-8i controller card also has the following features:

  • RAID levels 0, 1, 5, and 6
  • RAID spans 10, 50, and 60
  • Online Capacity Expansion (OCE)
  • Online RAID Level Migration (RLM)
  • Auto resume after loss of system power during array rebuild or reconstruction
  • Single controller multipathing
  • Load balancing
  • Configurable stripe size up to 1 MB
  • Fast initialization for quick array setup
  • Check consistency for background data integrity
  • Solid-state drive (SSD) support with SSD GuardTM technology
  • Patrol read for media scanning and repairing
  • 64 logical drive support
    • Global and dedicated hot spare with revertible hot spare support
    • Automatic rebuild
    • Enclosure affinity
  • Emergency SATA hot spare for SAS arrays

Conclusion

This article described how you can configure and use the MegaRAID-9361 controller card. The article also described its features and how you can use this controller card on an OpenPOWER system.