Bug ID 429896: CPU fans appear to run at double speed.

Last Modified: Jul 12, 2023

Affected Product(s):
BIG-IP EUD(all modules)

Known Affected Versions:
11.4.1

Opened: Sep 05, 2013

Severity: 5-Cosmetic

Symptoms

When booting a blade to the EUD application and running the 'sensor' test, then booting back to BIG-IP system, the CPU fans for that blade appear to be running at double their true speed. The fans are not actually spinning that fast. This is a reporting error only.

Impact

There is no physical impact to the CPU fans because the fans are not actually spinning that fast. The CPU fans normally spin at 6600 to 7200+ RPMs. In the error condition, the fans appear to be running anywhere from 13500 to 14400 RPMs. This is a reporting error only. Although the reporting of the fan speed appears doubled, the fans are still operating at their nominal speed of 6600 to 7200+ RPMs.

Conditions

To make the error condition appear, the blade must be booted into the EUD application. In the EUD application, run the sensor validation test, option #2. After that test completes, select the option to quit and reboot the system. When the blade boots back into BIG-IP system, the CPU fans will show double the speed of the EUD sensor test.

Workaround

To work around this issue, do one of the following: -- Have a serial console open to the blade running EUD and open the AOM command menu using ESC ( keystroke combination. Select to RESET the blade from that menu. -- Pull the blade from the slot and wait 10 seconds, then re-insert the blade.

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips