Bay Networks Remote Annex 4000, Hardware Installation Manual

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Remote Annex 4000 Hardware Installation Guide
Chapter 3 ROM Monitor Commands
3-22
net
The net command executes an Ethernet transceiver loopback test on
the local area network. The command syntax is:
net
The net command display looks like this:
This transceiver loopback test sends out a short test packet from the
Remote Annex 4000 through the transceiver to test the integrity of the
network. The test can be executed either by attaching the Remote
Annex 4000 to the Ethernet or by attaching an Ethernet loopback
connector to the network port.
For the 10Base2 and 10Base5 network interfaces, the preferred method
for running an Ethernet transceiver loopback test is to attach the
loopback connector to the network port because short test packets can
interfere with normal network traffic. The accessory kit supplies
Ethernet loopback connectors for these interfaces.
The 10BaseT network interface does not require a loopback connector
because it provides a Link Integrity LED next to the RJ45 connector.
This LED verifies that the receive circuit to the wiring concentrator is
operating correctly. If this LED is not lit, link LED impulses are not
present on the receive line due to a disconnected cable or some other
link failure.
The Ethernet transceiver loopback test causes the Net LED to turn off.
If the unit passes this test, the Net LED turns on and the console
displays PASSED. If the Remote Annex 4000 fails, the Net LED
remains off, and the console displays an error message.
monitor:: net
Network test – PASSED