228 Chapter6·AdvancedSystemAdministrationandTroubleshooting Introduction "Let's take a minute so I can explain how the IPSO boot manager works, as well as some of the things we can do at the command line," said Shin. "Can you explain how Mark can reset his password when he locks himself out?" asked Marty. "Very funny," responded Mark. "It only happened the one time." Marty laughed. "How long did that take again?" Mark frowned. "Only 4 days," responded Ming, rolling her eyes. "I figured it out, Ming," Mark quickly replied. "It just took...some time." "I'll also introduce you to the Command Line Interface Shell, more commonly referred to as CLISH," said Shin. "I hear from Marty that you both are fairly handy at the Cisco PIX command interface." Shin wanted to make sure Mark's pride wasn't hurt and thought it might do well to stroke his ego a bit. "Why, yes," Mark replied. "Ming and I have been working with Cisco hardware for years." Shin smiled. "Well, I think you will really enjoy this method of configuring the system then." Understanding the Boot Manager The boot manager is a small program that runs just after system startup, but before the IPSO kernel is loaded into memory. The Nokia boot manager is present on the system hard drive or in flash memory depending on the model. Without any interruption, the boot manager will bootstrap the system with the default kernel image, but it can be interrupted and given options from a rudimentary command shell. This functionality is typically useful to boot into single-user mode for system maintenance, or for reinstalling the operating system to factory defaults. Understanding Boot Manager Variables The boot manager operates by referencing some user-definable variables that are given sensible defaults when your Nokia device is shipped. Table 6.1 lists each variable and its purpose. This section discusses how to change the values of these variables.