Specifications
Replacing Parts
Cisco MGX 8220 Reference, Release 4.1
8-2
General Troubleshooting Procedures
The MGX 8220 shelf run self tests continuously to ensure proper function. When the unit finds an
error condition that affects its operation, it downs the card or line that is affected. If it is caused by a
card failure and there is a redundant card, the failed card is downed and the standby card becomes
the active card.
The FAIL lights on the cards indicate that the system has found these cards defective in some mode,
and now considers them as failed cards. Refer to Table 8-1 to find the cause and obtain information
on replacing the failed component.
Table8-1 Troubleshooting the MGX 8220 Shelf Node
Replacing Parts
After an alarm occurs, use the MGX 8220 shelf software to isolate the problem. If an MGX 8220
shelf part has failed, it must be replaced.
Caution Only authorized personnel should remove and replace parts on the MGX 8220 system.
Parts should be replaced personnel who have taken Cisco training courses or have been trained by a
qualified system manager. For assistance in diagnosing or replacing a failed part, call a Cisco
representative.
Symptom Probable Cause Remedy
No front panel LEDs are
lighted.
Circuit breakers on the MGX 8220 shelf
Power Entry Module(s) switched off.
Press in the black button on power entry modules to switch on
circuit breakers. If problem persists, pull all cards and power
supplies out to see if a shorted card or supply exists.
The MGX 8220 shelf power cord plug
disconnected from AC supply.
Reconnect power cord.
Card front panel
fail LED lit Card failed self-test. Check status of card at control console using dspcds screen.
If alarm is confirmed, try card reset (
resetcd command).
Finally, remove and replace the card.
Card
stby LED on. Card is off-line. Not a problem as long as a primary card is active.
BNM
major or minor LED on. Service-affecting (major) or non-service
affecting (minor) system fault.
Check event log to identify problem reported.
Network trunk failed. Observe
Port LEDs on each BNM.
Use control console
dspln to locate failure.
Internal temperature is higher than
normal resulting from blocked air flow
or defective fan.
Check front of cooling assembly for freedom of air flow.
Replace the assembly that may have failed or slowed. Check
free air flow in plenum chamber, remove blockage if
necessary.
ASM
hist LED lit. If no other alarm indications, a fault
occurred in the past but has been cleared.
Press ASM history clear button. Check NMS event log to
determine cause.
BNM
Port LED is red. Trunk is in local or remote alarm. Use short BNM loopback cable line module connector for
local test of trunk. Loop trunk at DSX-3 crossconnect to
check cable.
ASC
fail LED flashing Downloading system software or
configuration data.
Wait for download to complete.