Appendix C: General Parameters and Modules

This appendix is provided to illustrate some of the possible parameters available for some common hardware device drivers. A driver is software enabling your system to use a particular hardware device. Without the driver, the kernel may not know how to access the device correctly. In most cases, these additional parameters are unnecessary, since the kernel may already be able to use the device without them. You should use the settings provided in this appendix only if you are having trouble getting Red Hat Linux to use a particular device or you need to override the system’s default parameters for the device.

During the installation of Red Hat Linux, some limits are placed on file systems and some device drivers supported by the kernel. After installation, however, support exists for all file systems available under Linux. At the time of installation, the modularized kernel has support for (E)IDE devices (including ATAPI CD-ROM drives), SCSI adapters, and network cards.

Note

Because Red Hat Linux supports installation on many different types of hardware, some drivers (including those for SCSI adapters, network cards, and many CD-ROMs) are not built into the Linux kernel used by the installation program. Rather, they are available as modules and are loaded as you need them during the installation process. If necessary, you will have the chance to specify options for these modules when they are loaded from the driver disk.

To specify module parameters when a driver is loaded, type linux expert at the boot: prompt and insert the driver disk when prompted to do so by the installation program. After reading the driver disk, the installation program will ask you to select the type of device you are configuring. On that screen, you can elect to specify a module parameter. Then, the installation program will display a screen where you can type the correct parameters based on the particular type of device you are configuring.

After the installation is complete, you may want to rebuild a kernel that includes support for your specific hardware configuration. Note that in most cases, a custom-built kernel is not necessary.

Cross-reference

See Chapter 12 for more information about rebuilding your kernel.

Specifying Module Parameters

If you are providing parameters upon loading a module, you can usually specify them using one of two methods:

• Specify a full set of parameters in one statement. For example, the parameter cdu31=0x340,0 could be used with a Sony CDU 31 or 33 at port 340 with no IRQ.

• Specify the parameters individually. This method is used when one or more parameters in the first set are not needed. For example, cdu31_port=0x340 cdu31a_irq=0 can be used as the parameter for the same CD-ROM used as an example for the first method. An OR is used in the CD-ROM, SCSI, and Ethernet tables in this appendix to show where the first parameter method stops and the second method begins.

  Note

  Use only one method, not both, when loading a module with particular parameters.

  Warning

  When a parameter has commas, make sure you do not put a space after a comma.