In this chapter, we examined the processes involved in booting up an SLES server. The major steps are the POST, BIOS, initrd, the boot loader, the kernel load, and the init process. A proper understanding of the role of each process will facilitate the diagnostic phase should a failure occur.
When a system shutdown is required, it is important to ensure that the shutdown is performed in a controlled manner to avoid file corruption and data loss. There are several options available for halting a system. The preferred method is to use the shutdown command. This utility provides for the proper notification of the shutdown to system users.
We also introduced the steps necessary to provide alternate access to the system should a problem arise in the startup process. Additional techniques for recovery are discussed in Chapter 10.