Use Loopback Testing for T1 Interfaces

This chapter describes using loopback testing to isolate T1 interface problems.

• Checklist for Using Loopback Testing for T1 Interfaces
• Diagnose a Suspected Hardware Problem with a T1 Interface
• Create a Loopback
• Set Clocking to Internal
• Verify That the T1 Interface Is Up
• Clear T1 Interface Statistics
• Force the Link Layer To Stay Up
• Verify the Status of the Logical Interface
• Ping the T1 Interface
• Check for T1 Interface Error Statistics
• Diagnose a Suspected Circuit Problem