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Monitoring the DSU
6-3
7612-A2-GB20-10
November 1997
System LEDs
496-1506
2
CTS (106)
OK
ALARM
TEST
DM
OOS
OOF
NS
TXD (103)
RXD (104)
RTS (105)
DTR (108)
NetworkSystem
Port
red green yellow
OK:
ON – DSU is operational.
OFF – DSU has detected a system failure, or there is
no power.
ALARM:
ON – DSU has detected an alarm condition locally or from
the network. Refer to Chapter 8,
Messages and
Troubleshooting
.
TEST:
ON – Test in progress. Test can be initiated locally, remotely,
or from the network. Includes power-up self-test.