CANOGA PERKINS 9145EMP Network Interface Device Hardware - Manual (Page 44)

9145EMP Network Interface Device Hardware User’s Manual Troubleshooting
Loopback Diagnostics
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5.4 Loopback Diagnostics
Use Loopbacks to diagnose a fault on the optical link. Loopbacks can be set at any port; once a
port is in loopback mode, data is looped at the physical level though the particular port. When
performing loopback diagnostics, the 9145EMP uses a unique MAC address, designated as the
Loop Test MAC Address, which is displayed on the Loopback Setup Screen (see the 9145EMP
NID Software User’s Manual). When in loopback mode, the 9145EMP filters and discards all ser-
vice frames. Only packets with the predefined Loop Test MAC Address are looped back
The 9145EMP is configurable to swap the origination and destination MAC Addresses and to
recalculate the looped frame's CRC. Test packets are returned to the source according to the
selected options.
To display current loopback status, configure address swapping and CRC recalculation options,
see the 9145EMP NID Software User’s Manual.