ZyXEL Communications MSC1000G Series, User Manual

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Chapter 23 diagnostic Commands
Management Switch Card User’s Guide
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The command then displays the results of the ADSL port loop diagnostics.
23.4.5 diagnostic ldm test Command
Syntax:
diagnostic ldm test < slot-port >
This command has the system perform a Loop Diagnostic Mode test. This is a Dual End Loop Test
(DELT). It provides details about the condition of the line on the specified ADSL or VDSL port. The
ADSL port must be set to ADSL, ADSL2 or ADSL2+ operational mode and have a connection. The
VDSL port must be set to VDSL2, ADSL2 or ADSL2+ operational mode and have a connection. Use
the loop diagnostics results to analyze problems with the physical ADSL or VDSL line. The
subscriber device must also support DELT in order to perform this. This feature is applicable for ALC
or VLC line cards only.
It takes about one minute for the loop diagnostics to finish.
The following example performs loop diagnostics on DSL port 4 of the line card in slot 2. The
command then displays the results of the DSL port loop diagnostics.
23.4.6 diagnostic loopback f5 Command
Syntax:
diagnostic loopback f5 < slot-port-vpi/vci >
This command has the system perform an OAMF5 loopback test on the specified virtual circuit. An
Operational, Administration and Maintenance Function 5 (OAMF5) test is used to test the
connection between two DSL devices. First, the DSL devices establish a virtual circuit. Then the
local device sends an ATM F5 cell to be returned by the remote DSL device (both DSL devices must
support ATM F5 in order to use this test).
The following example has the system perform a local loopback test on a virtual circuit on DSL port
5 of the line card in slot 7. The virtual circuit is identified by VPI 0 and VCI 33.
ras> diagnostic ldm show 5-4 result
port 5-4:
near end far end
------------ ------------
attainable bit rate(kpbs): 1420 26060
loop attenuation(dB) : 1.6 0.0
signal attenuation(dB) : 0.5 0.0
snr margin(dB) : out of range out of range
actual tx power fe(dBm) : 11.7 10.1
ras> diagnostic ldm test 2-4
ras> diagnostic loopback f5 7-5-0/33
line 1 oam loopback success!