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Solution
Follow these guidelines to troubleshoot the fans:
• Check the status LED on the fan tray and the alarm LED on the front panel.
If the alarm LED on the front panel glows, use the CLI to get information about the source of an
alarm condition:
user@switch> show chassis alarms
If the CLI output lists only one fan failure and the other fans are functioning normally, the fan is most
likely faulty and you must replace the fan tray. You cannot replace a single fan. If one or more fans
fail, you must replace the entire fan tray.
• Place your hand near the exhaust vents at the side of the chassis to determine whether the fans are
pushing air out of the chassis.
• If a fan tray is removed, both a minor alarm and a major alarm occur.
• The following conditions automatically cause the fans to run at full speed and also trigger the
indicated alarm:
• A fan fails (major alarm).
• The switch temperature exceeds the
temperature warm threshold (minor alarm).
• The temperature of the switch exceeds the
temperature hot threshold (major alarm and automatic
shutdown of the power supplies).
Troubleshooting the Power Supply in an EX9253 Switch
IN THIS SECTION
161