Cisco Systems, Inc. All rights reserved. Important Information Important Information This section contains information about the following hardware and software requirements: • Router Information • Cisco IOS Software Requirements • Product Overview Router Information For hardware installation and maintenance information on Cisco 12000 Series Routers, refer to the installation and configuration guide for your router. This includes information on card slot locations and other general requirements.

Caution To avoid confusion and possibly halting the Cisco 12000 Series Router, remember that valid configuration register settings might be combinations of settings and not just the individual settings listed in Table 9. For example, the factory default value of 0x2102 is a combination of settings. 30 Implementing Additional Configuration and Maintenance Tasks 78-4339-09 Implementing Additional Configuration and Maintenance Tasks Table 9 Software Configuration Register Bit Descriptions Bit 1 Hex