Cisco 10000 Series

CHAPTER
6-1
Cisco 10000 Series Router Troubleshooting Guide
OL-0439-02
6
Troubleshooting Serial Lines
This chapter describes methods for detecting and correcting data errors on the Cisco 10000 series router
serial interfaces.
Optical Signal Input/Output Problems
Signal input and output problems can occur at any point in the network and can be caused by mechanical
defects in cables or fiber, poor connections, or loss of signal caused by other equipment failures. Refer
to your site log and other facility records to isolate signal connections for your facility.
Fiber-Optic Connections
An optical signal I/O problem can be caused by:
• Incorrect type of fiber
• Defective fiber
• Transmit (TX) and Receive (RX) fibers that are reversed
• Insufficient power budget on the optical link
• Receiver overload on the optical link
Be sure to use single-mode fiber for a single-mode interface and multimode fiber for a multimode
interface. Table 6-1 describes the fiber types appropriate for each Cisco 10000 series router line card.