Nexus 3K airflow direction

[vikaspurohit11]

Hello All,

We are in serious trouble. We have ordered the Nexus3K N3K-C3524P-10GX with incorrect airflow direction and we are nearing implementation. Can we replace the fan module and power supplies or we need to order new switches.

Please help.

Regards,

Vikas Purohit

[Seb Rupik · Accepted solution]

Hi there,

You will need to replace the four fan modules and two power supplies, not even Cisco is cruel enough to make you replace the entire switch! ;)

NXA-FAN-30CFM-F	N2K/3K Individual Fan, Forward airflow (port side exhaust)
NXA-FAN-30CFM-B	N2K/3K Individual Fan, Reversed airflow (port side intake)
N2200-PAC-400W	N2K/3K 400W AC Power Supply, Forward airflow (port side exhaust)
N2200-PAC-400W-B	N2K/3K 400W AC Power Supply, Reversed airflow (port side intake)
N2200-PDC-400W	N2K/3K 400W DC Power Supply, Forward airflow (port side exhaust)
N3K-PDC-350W-B	N2K/3K 350W DC Power Supply, Reversed airflow (port side intake)

cheers,

Seb.

[vikaspurohit11]

Thanks a lot.

[yassirromero7961]

I have a similar issue with a stack of Nexus C9300-48P.

What fan modules and power supplies would be recommended to convert the switches to Forward-airflow?

Your input would be very helpful to this project.

[Seb Rupik]

Hi there,

I haven't seen any part numbers for the 9300 which indicate it supports any other air flow other than front-to-back.

The installation guide states:

"The airflow patterns vary depending on the power supply configuration."

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/hardware/install/b_c9300_hig/b_c9300_hig_chapter_01001.html#reference_D7D85EC38BBE49BAB3A44320EEDC9192

...however, unlike other switches there is only on a handful of PSU available with no indication of supports a different airflow direction.

https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9300-series-switches/data_sheet-c78-738977.html#Orderinginformation

Can you not just rotate the switch 180 degrees in the cabinet?

cheers,

Seb.

[bhagen]

I realize this is an *old* post, but...I'm now in the same situation (I have the Nexus 3172T switches).

Did you get the fans swapped? If yes, is there a command you had to run first to make it happen?

I have the fans and power supplies that blow the "other" way, but when I attempted to hot-swap the fans I got the “fan-direction mismatch, shutting down in 60 seconds” messages, so I had to swap them back.

All I can find is that there's a “no system shutdown fan-direction mismatch” command, but there's no info about it that I can find.

[Seb Rupik]

Hi there,

Whilst the Nexus is reporting the fan direction mis-match, what is the output of:

sh environment fan det

Also what platform and NX-OS version are you using?

cheers,

Seb.

[bhagen]

---

@Seb Rupik wrote:

Hi there,

Whilst the Nexus is reporting the fan direction mis-match, what is the output of:

sh environment fan det

Also what platform and NX-OS version are you using?

cheers,

Seb.

---

Thanks for the reply!

I'm not able to get that info, as I'd have to take a production switch down again to get it...not a happy thought. :-)

I opened a case with TAC after I posted this, and the answer for me is "Maintenance Window": shut down all 4 switches, swap the fans and power supplies, then power them back up. I'll be trying that in a few days, after hours.