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AMI(4) Device Drivers Manual AMI(4)

amiAmerican Megatrends Inc. MegaRAID PATA/SATA/SCSI RAID controller

ami* at pci?

The ami driver provides support for the MegaRAID family of RAID controllers, including:

These controllers support RAID 0, RAID 1, RAID 5, JBOD, and superpositions of those configurations.

Although the controllers are actual RAID controllers, the driver makes them look just like SCSI controllers. All RAID configuration is done through the controllers' BIOSes.

RAID management is done through the bio(4) device with the bioctl(8) command. Logical disk status is exposed under the hw.sensors sysctl(8) and can be monitored using sensorsd(8). For example:

$ sysctl hw.sensors.ami0
hw.sensors.ami0.drive0=online (sd0), OK
hw.sensors.ami0.drive1=degraded (sd1), WARNING
hw.sensors.ami0.drive2=failed (sd2), CRITICAL

bio(4), intro(4), pci(4), scsi(4), sd(4), bioctl(8), sensorsd(8), sysctl(8)

The ami driver first appeared in OpenBSD 2.9.

The ami driver was written by Michael Shalayeff <>.

Management functions were implemented by Marco Peereboom <>.

February 19, 2022 OpenBSD-7.4