Cisco Nexus 9504 - Overview of Fan Trays

Before you begin
For grid redundancy mode, the power supplies must be divided into two equal sets and installed as follows:
• Slots PS 1 and PS 2 must be connected to one grid (Grid A).
• Slots PS 3 and PS 4 must be connected to another grid (Grid B).
Step 1 Use the configure terminal command to enter the global configuration mode.
Example:
switch# configure terminal
switch(config)#
Step 2 Use the power redundancy-mode mode command to specify one of the following power modes:
• For combined mode, include the combined keyword.
• For n+1 redundancy mode, include the ps-redundant keyword.
• For n+n redundancy mode, include the insrc-redundant keyword.
Example:
switch(config)# power redundancy-mode insrc-redundant
switch(config)#
Overview of Fan Trays
Fan trays provide airflow through the switch for cooling. Each fan tray contains multiple fans to provide
redundancy. The switch can continue functioning in the following situations:
• One or more fans fail within a fan tray—Even with multiple fan failures, the switch can continue
functioning. When a fan fails within a tray, the functioning fans in the module increase their speed to
compensate for the failed fans.
• The fan tray is removed for replacement—The fan tray is removed and replaced while the switch is
operating without presenting an electrical hazard or damage to the switch. The switch can operate for
three minutes without the fan tray that you are replacing, but if the switch air-inlet temperature is less
than 86 degrees Fahrenheit (30 degrees Celsius), you have up to 72 hours to replace the fan tray. Because
temperatures can change over time, we recommend that you replace the fan tray within three minutes.
• If you remove more than one fan tray at a time, the switch can operate up to three minutes before shutting
down. To prevent a shutdown, remove only one fan tray at a time.
When a fan fails or when you remove a fan tray, the remaining operating fans speed up to compensate
for the loss of fans. This process can increase the noise that is made by the fan trays until you replace
the missing fan tray or replace the defective fan tray.
Note
Cisco Nexus 9504 NX-OS Mode Switch Hardware Installation Guide
69
Managing the Switch
Overview of Fan Trays