Troubleshooting Basic Cisco IPC Express Features

This chapter covers the following topics:

• Understanding the phone bootup sequence
• Understanding the messages on the phone display
• Debugging virtual LAN (VLAN), Dynamic Host Configuration Protocol (DHCP), Trivial File Transfer Protocol (TFTP), and other registration issues
• Upgrading phone loads with signed and unsigned loads
• Troubleshooting basic call setup and teardown issues
• Troubleshooting Cisco IP Communications (IPC) Express graphical user interface (GUI) issues

Parts II and III of this book covered Cisco IP Communications (IPC) Express features, applications, and management. In Part IV the focus turns to troubleshooting tools and techniques for Cisco IPC Express. The first three chapters of Part IV focus on Cisco CallManager Express (CME), and the last three concentrate on Cisco Unity Express (UE).

Cisco CME provides a range of troubleshooting tools to isolate the cause of problems that might occur. Issues can range from simple situations, such as getting a phone registered to Cisco CME to more complex scenarios, such as overlay-dns and huntgroup configurations not operating correctly. Quite often you can correct problems with small configuration changes or by adjusting the system's operation to be closer to the expected behavior.

Troubleshooting a Cisco CME system requires an understanding of the following:

• The Cisco CME system architecture and its integration with the Cisco IOS voice architecture. This was covered in Chapter 3, "Cisco IPC Express Architecture Overview."
• The phone registration process.
• Cisco CME debug commands.

This chapter explores some basic troubleshooting topics, such as phone bootup and registration, VLAN configurations, Trivial File Transfer Protocol (TFTP) and call setup and teardown, and GUI issues. Subsequent chapters take a closer look at specific features and applications of the system.