CANOGA PERKINS 9145ELB NID Software Version 4.01 - Manual (Page 56)

9145ELB NID Software User’s Manual Diagnostics
Loopback Setup
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4.1 Loopback Setup
The Loopback Setup screen is used to configure and initiate loopback diagnostics. Packets sent
to the 9145ELB with a destination MAC address equal to the Loop Test MAC address will be
looped back by the 9145ELB Port that has been placed into loopback mode. Packets received
with any other destination MAC address will be discarded. The 9145ELB can be configured to
swap source and destination MAC addresses of the test packets and to recalculate the CRC of
the packet after the MAC addresses are swapped, so the packet that has been looped back can
successfully be switched through the network back to the equipment that originated the test.
Loopback can be enabled only on one port at a time. Loopback must be cleared before placing
another port into loopback mode.
Figure 4-2 Proprietary MAC Loopback
To configure Loopback, on the Diagnostics menu, type 1 and press Enter. The Ethernet
Loopback Setup screen (Figure 4-3) opens.