The switch will shut down if a mix of Gen 1 (N77-C7718-FAN) and Gen 2
(N77-C7718-FAN-2) fan trays are present in the same switch for more than 21600
seconds (6 hours). The syslog message "PLATFORM-0-FAN_MISMATCH_TIME:
Mismatch of Fan modules. Both Gen1 and Gen2 fans are present in the fantray for
<number> seconds" will be displayed at regular intervals when both Gen 1 and Gen 2
fan trays are present in the same switch.
Note
•
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.
Note
•
We recommend that you do not remove more than 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 can increase the noise made by
the fan trays until you replace the missing fan tray or replace the defective fan
tray.
•
When replacing a failed fan tray in a running system, be sure to promptly replace
the fan tray.
If one or more fans fail within a fan tray, the Fan Status LED turns red. A fan failure could lead to
temperature alarms if not corrected immediately.
Caution
The fan status is continuously monitored by the software. In case of a fan failure, the following actions occur:
•
System messages are displayed.
•
Call Home alerts are sent (if configured). For more information, refer
Associating an Alert Group with
.
•
SNMP notifications are sent (if configured). For more information, refer
.
.
Each of the three fan trays cover two fabric modules as follows:
•
Fan tray in slot 41 covers the fabric modules in slots 21 and 22.
•
Fan tray in slot 42 covers the fabric modules in slots 23 and 24.
•
Fan tray in slot 43 covers the fabric modules in slots 25 and 26.
If you need to replace a fabric module, you must remove the fan tray covering the fabric module before you
replace the fabric module. You must replace the fabric module and its covering fan tray within three minutes
or an overtemperature condition can occur.
Cisco Nexus 7718 Switch Site Preparation and Hardware Installation Guide
OL-30453-01
101
Managing the Switch
Overview of Fan Trays