Automatic Configuration of Devices

The kernel consists of a small generic core with a platform-specific component and a set of modules. The kernel is configured automatically in the Solaris release.

A kernel module is a hardware or software component that is used to perform a specific task on the system. An example of a loadable kernel module is a device driver that is loaded when the device is accessed.

The platform-independent kernel is /kernel/genunix. The platform-specific component is /platform/`uname -m`/kernel/unix.

The kernel modules are described in the following table.

Table 5–2 Description of Solaris Kernel Modules

Location	Directory Contents
/platform/`uname -m`/kernel	Platform-specific kernel components
/kernel	Kernel components common to all platforms that are needed for booting the system
/usr/kernel	Kernel components common to all platforms within a particular instruction set

The system determines what devices are attached to it at boot time. Then, the kernel configures itself dynamically, loading needed modules into memory. At this time, device drivers are loaded when devices, such as disk devices and tape devices, are accessed. This process is called autoconfiguration because all kernel modules are loaded automatically when they are needed.

You can customize the way in which kernel modules are loaded by modifying the /etc/system file. For instructions on modifying this file, see system(4).

Features and Benefits of Autoconfiguration

The benefits of autoconfiguration are as follows:

• Main memory is used more efficiently because modules are loaded when needed.

• There is no need to reconfigure the kernel when new devices are added to the system.

• Drivers can be loaded and tested without having to rebuild the kernel and reboot the system.

Autoconfiguration is used when you add a new device (and driver) to the system. At this time, you might need to perform reconfiguration boot so that the system recognizes the new device unless the device is hot-pluggable. For information about hot-plugging devices, see Chapter 6, Dynamically Configuring Devices (Tasks).

What You Need for Unsupported Devices

Device drivers needed to support a wide range of standard devices are included in the Solaris release. These drivers can be found in the /kernel/drv and /platform/`uname -m`/kernel/drv directories.

However, if you have purchased an unsupported device, the manufacturer should provide the software that is needed for the device to be properly installed, maintained, and administered.

At a minimum, this software includes a device driver and its associated configuration (.conf) file. The .conf files reside in the drv directories. This software might also include custom maintenance and administrative utilities because the device might be incompatible with Solaris utilities.

For more information about what you need for unsupported devices, contact your device manufacturer.