| You may need to modify your HP-UX 11i kernel in some way, such as changing a kernel parameter, and then rebuild your kernel. You may need to create a new HP-UX kernel in order to add device drivers or subsystems, to tune the kernel to get improved performance, to alter configurable parameters, or to change the dump and swap devices. If you update or modify a dynamic element of your kernel, as shown in the example in this chapter, a reboot is not required. Updating or modifying a static element requires a reboot and may also require some additional steps. With HP-UX 11i it is not necessary to rebuild your kernel for all changes that take place to it. In 11i, there are many Dynamically Tunable Kernel Parameters and Dynamically Loadable Kernel Modules that will modify your kernel but not require a reboot. Combined with many Dynamic Patches that are available in 11i, you will need to reboot your system less often. In the next section, we'll modify a Dynamically Tunable Kernel Parameter, thereby modifying the kernel, and do not have to reboot the system in order for the change to take place. We'll then make a change to the kernel and fully rebuild it so that you can see the process of a complete rebuild, including a reboot. I normally use the System Administration Manager (SAM) covered in Chapter 11 to make kernel modifications. There is, however, no substitute for understanding the process by which you would manually build an HP-UX kernel and, therefore, be more informed when you have SAM do this for you in the future. In this chapter, I discuss various commands related to kernel generation and cover the process by which you would manually create a kernel. |
