---
name: "isci"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/isci"
---

# isci(4)

Intel C600 Serial Attached SCSI driver

## NAME

**isci** – Intel C600 Serial Attached SCSI driver

## SYNOPSIS

To compile this driver into your kernel, place the following lines in your kernel configuration file:

**device scbus** **device isci**

Or, to load the driver as a module at boot, place the following line in [loader.conf(5)](/loader.conf/5.md):

```
isci_load="YES"
```

## HARDWARE

The **isci** driver provides support for Intel C600 SAS controllers.

## CONFIGURATION

To force legacy interrupts for all **isci** driver instances, set the following tunable value in [loader.conf(5)](/loader.conf/5.md):

```
hw.isci.force_legacy_interrupts=1
```

## DEBUGGING

To enable debugging prints from the **isci** driver, set the

```
hw.isci.debug_level
```

variable to a value between 1 and 4 in [loader.conf(5)](/loader.conf/5.md).

The hardware layer in the **isci** driver has extensive logging capabilities which are disabled by default for performance reasons. These can be enabled by adding

```
options ISCI_LOGGING
```

to the kernel configuration file.

## SEE ALSO

[cd(4)](/cd/4.md), [ch(4)](/ch/4.md), [da(4)](/da/4.md), [pci(4)](/pci/4.md), [sa(4)](/sa/4.md), [scsi(4)](/scsi/4.md)

## HISTORY

The **isci** driver first appeared in FreeBSD 8.3 and 9.1.

## AUTHORS

The **isci** driver was developed by Intel and originally written by Jim Harris ⟨*jimharris@FreeBSD.org*⟩ with contributions from Sohaib Ahsan and input from Scott Long ⟨*scottl@FreeBSD.org*⟩.

This man page was written by Jim Harris ⟨*jimharris@FreeBSD.org*⟩.