Technical Tip: FortiSwitch FAN failure

vpatil · ‎12-14-2020

Description
This article describes how to detect and debug FortiSwitch FAN failure.

Scope
The FortiSwitch can function fine temporarily, but the Forti Switch temperature can rise eventually if the FAN stops spinning and also if the FortiSwitch rack room temperature is not maintained by proper Cooling Systems.

Solution
1) Check if the FortiSwitch front panel shows any Amber LED.

Example: FSW-424E quick start guide - Alarm LED ‘Amber’ indicates - The unit has a fault
Page 8: https://pub.kb.fortinet.com/ksmcontent/Fortinet-Public/current/FortiSwitch_HW/FortiSwitch-424E-Serie...

2) The below outputs from FortiSwitch might show 'FAN failure detected' alarms as shown below:

# diagnose sys fan status

Module Status
___________________________________
Fan alarmed Last status(50.2 %)

# diag sys pcb temp

Module Status
___________________________________
Sensor1 63.0 C
Sensor2 58.1 C

# execute log display

2020-09-30 06:18:39 log_id=0103033100 type=event subtype=system pri=warning vd=root action="state-change" user="ctrld" ui="None" msg="FAN failure detected"

3) There are known Fan related anomalies on older FortiSwitch firmware versions such as v3.5.x and v3.6.x and also on v6.4.0 and Bug 625325 - After upgrading an FSW-1048E switch to FortiSwitchOS 6.4.3, the fan speed was very high - Bug 675444 is fixed in FortiSwitchOS v6.4.4 and higher release.

Page 17: https://fortinetweb.s3.amazonaws.com/docs.fortinet.com/v2/attachments/13d93bbb-204d-11eb-96b9-005056...

4) To rule-out FortiSwitch firmware issue, if feasible - upgrade affected FortiSwitch to FortiSwitchOS v6.4.4 and higher release and then check the Fan status (# diagnose sys fan status).

Note: Download FortiGate config backup and FortiSwitch config backup (for Standalone FortiSwitch) before attempting FortiSwitch firmware upgrade.

5) Factory-reset the FortiSwitch using the FortiSwitch Reset button (Press and release the button after one minute) or via CLI command (# execute factoryreset) and thereafter check the FortiSwitch Fan status.

Contact Fortinet Support for any questions with affected FortiSwitch Serial Number (# get system status) and below logs: https://www.fortinet.com/support/contact

Reference.

FortiSwitch commands:

# diagnose sys fan status
# diag sys pcb temp
# get hardware status
# execute log display
# diag debug report