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Change from front-to-back to back-to-front cooling on catalyst 4500-X

Level 1
Level 1


I have a additional fan and power supply kit for our new 4500-X core switch. I wanted to change the fan's but I got en error message on the console line and the fan indicated the red light.

The log sends following error

Feb 23 09:47:02.416: %C4K_IOSMODPORTMAN-4-AFANTRAYREMOVED: Fan tray 5 has been removed
Feb 23 09:47:17.420: %C4K_IOSMODPORTMAN-6-AFANTRAYINSERTED: Fan tray 5 has been inserted
Feb 23 09:47:19.420: %C4K_IOSMODPORTMAN-4-AFANTRAYBAD: Fan tray 5 has failed
Feb 23 09:47:19.420: %C4K_CHASSIS-3-SUPERVISORFANTRAYPARTIALFAILURE: A fantray, among the currently installed fantrays, is not functioning.

show env

Fan trays needed by system    : 4
Fan trays currently available : 5
Chassis fan tray direction    : FrontToBack

Fantray 1 : dir : FrontToBack    status : Good
Fantray 2 : dir : FrontToBack    status : Good
Fantray 3 : dir : FrontToBack    status : Good
Fantray 4 : dir : FrontToBack    status : Good
Fantray 5 : dir : BackToFront    status : Failure

Any ideas or procedures for changing the fans and the Power Supplies? Is there an command to change in the config? Or is the change only possible with a powerd-off Switch?

Thanks for help


1 Reply 1

Ich Nafi
Level 1
Level 1

Four fans Front2Back and one Fan Back2Front doesn't make sense to me and obviously not to the switch. You have to use the same Fans. (B2F and F2B are two different Products!)

See this link:

The chassis determines which airflow direction is correct by polling all of the fan assemblies and the power supplies. The airflow direction for all of the devices must be the same. If the airflow direction of the replacement fan assembly does not match the other fan assemblies airflow direction or the power supply airflow direction, the system software shuts down the power supply and generates an error message to the console.

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