Reference Guide

Recognize an Over-Temperature Condition
An overtemperature condition occurs, for one of two reasons: the card genuinely is too hot or a sensor has
malfunctioned.
To discover the cause, inspect cards near the one reporting the condition.
• If directly adjacent cards are not normal temperature, suspect a genuine overheating condition.
• If directly adjacent cards are normal temperature, suspect a faulty sensor.
When the system detects a genuine over-temperature condition, it powers off the card. To recognize this condition, look
for the system messages shown in the following example.
FTOS#show alarms threshold
-- Temperature Limits (deg C) --
-------------------------------------------------
Minor Minor Off Major Major Off Shutdown
Linecard 75 70 80 77 85
RPM 65 60 75 70 80
FTOS#
Troubleshoot an Over-Temperature Condition
To troubleshoot an over-temperature condition, use the following commands.
1. To monitor the temperature levels, use the show environment commands.
2. Check air flow through the system. Ensure the air ducts are clean and that all fans are working correctly.
3. After the software has determined that the temperature levels are within normal limits, you can re-power the card
safely. To bring back the line card online, use the
power-on command in EXEC mode.
In addition, Dell Networking requires that you install blanks in all slots without a line card to control airflow for adequate
system cooling.
NOTE: Exercise care when removing a card; if it has exceeded the major or shutdown thresholds, the card could
be hot to the touch!
Recognize an Under-Voltage Condition
If the system detects an under-voltage condition, it declares an alarm.
To recognize this condition, look for the system messages shown in the following example.
%CHMGR-1-CARD_SHUTDOWN: Major alarm: Line card 2 down - auto-shutdown due to
under voltage
This message indicates that the specified card is not receiving enough power. In response, the system first shuts down
Power over Ethernet (PoE). If the under-voltage condition persists, line cards are shut down, then route processor
modules (RPMs).
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