Wired Intelligent Edge

AFAIK both Aruba 8320/8400X provide Fan(s) working with the Front-to-Back airflow direction rule.

Given that I'm not able to understand if there are specific Fan(s) Hardware designs restrictions on both platforms with regards to expected airflow...I've this question: Will airflow's direction management (Front-to-Back versus Back-to-Front) be ever supported through Software (supposing it is yet by Hardware) on these platforms as it happens on most HPE FlexFabric switch series?

We try to get an strict and common Hot/Cold airflow separation on each DC Rack we have but our Aruba 8320 pair (ToR), sharing the same Rack with SAN Storages/Switches designed to run with Back-to-Front airflow direction, is causing a weak undesired local airflow loop.

Up to now that is not worrying us too much - top Aruba 8320 internal temperatures are below 36°C despite its inlet air temperature isn't 16°C as it should be due to the airflow local loop (that's the supposed fresh inlet air temperature on the Rack backside) - it's just annoying since neighbour switches are capable of running colder by just respecting the set airflow direction.

As you can image...we can't simply reverse the Aruba 8320 mounting direction inside the Rack since FO cables arrive all at Rack backside (which is the frontside of all Switches).

WRT Aruba 8320: looking at Sunon Fan [*] assemblies supported on similar switching platform Accton AS5712-54x [**] and, provided that each Fan Assembly owns a fans pair which is suppling an IR E/R direction signal (0=Front-to-Back versus 1=Back-to-Front) acting as input for the Altera EPM570 MAX II CPLD mainboard IC, I suspect that Air Flow's direction in this particular platform is something that can't be simply driven by (ArubaOS-CX or whatever) OS (hope to be wrong here)...instead it depends strictly on how fans pair are mechanically mounted inside their Fan Assembly...and so the only way for each Fan Assembly to provide an inverted air flow is (a) use [***] a proper Back-to-Front Air-Flow direction Fan Assembly (AFAIK no HPE/Aruba SKU is available at present time) or (b) try an hack (I've read somewhere that someone really did that on a Aruba 8400X...) and manually invert Fans mounting sense inside each Fan Assembly (given that Fan Assembly frame lets us to do it, mechanically speaking).

Clearly option (b) is not something I feel to suggest here...just a for say.

[*] Aruba 8320 uses fIve of those ones with the description "Aruba X721 Front-to-Back fan" (HPE/Aruba SKU JL481A).

[**] Sunon Front-to-Back PF40561BX-Q020-S99 with Red hand and Sunon Back-to-Front PF40561BX-Q010-S99 with Blue hand.

[***] provided that that SKU is going to be marketed by HPE/Aruba.

Hello Davide,

Before getting back with an informative answer, let me clarify something about your statement:

"supported through Software (supposing it is yet by Hardware) on these platforms as it happens on most HPE FlexFabric switch series?"

 

With 5900/5930/5940 you have to select a B2F or a F2B FAN tray. You can not tune the rotation by software (even if you have to

set the proper direction in CLI to be compliant to installed hardware).

 

Hello Vincent, you're correct.

 

I tend to be too indulgent (or too optimistic) with HPE FlexFabric's features&capabilities.

 

So, yes, HPE FlexFabric switch series need correct Fan Trays SKUs to be installed (Front-to-Back or Back-to-Front, mix is supported)...nevertheless there is a Comware command (fan preferred air-flow) used to reconciliate/reconfigure air flows directions with preferred ones, if I'm not mistaken...I should have clarified I was referring about that.

The older Comware fantrays were not colour coded, and it was not always clear whether a fantray was FB or BF (the airflow direction arrow and the P/N help if you can read them!) That command is purely a verification to make sure that mismatched trays were not installed (potentially messing up airflows, and perhaps feeding hot air back into the switch).

Thanks! that's OK (sorry for confusion), nevertheless my question for Aruba 8320/8400X is still valid...

And after checking, there is no such developpment plan for 8400 and 8320. Thanks anyhow for great ideas and comments.

The solution is use 8325 :-) there is a model with Fan Front to Back and another for Back to Front !

Gosh...would be nice!

The Aruba 8325 has Front-to-Back and Back-to-Front on both Power Supply Modules and Fan Modules...but I don't think they're exchangeable with Aruba 8320...and I really can't exchange a pair of Aruba 8320 for a pair of Aruba 8325...at least until Aruba will knock the door to leave my company a Xmas present! in ant case we are pretty much tied to (a lot of) 10Gbps NICs...so Aruba 8320 fits the bill.

If a customer has an 8325 B2F model can they just purchase the F2B fans to convert it?  

Yes, but - in addition to F2B Fans - the F2B Power Supplies (JL632A) are
required too.

Sorry for dragging up this old topic, are there still no B2F fans for 8320s and not planned or did this change?

 

I find it kind of mind blowing that that would not be a standard offering on kit like this (maybe I'm spoiled coming off Mellanox kit)

Hi!

---

@Keeper of the Keys wrote: Sorry for dragging up this old topic, are there still no B2F fans for 8320s and not planned or did this change?

Unfortunately, none I'm aware of...and I've been in - sort of - "listening mode" for so long...and still I am.

 

---

@Keeper of the Keys wrote:I find it kind of mind blowing that that would not be a standard offering on kit like this (maybe I'm spoiled coming off Mellanox kit)

---

Yeah, especially considering what is the current offering of Fan/PS airflow options for the newer Aruba 8325...I found it too (kind of mind blowing).

 

Still - after such many months - I don't understand what is blocking Aruba about that (Isn't the Aruba 8320 a DC switch? Doesn't it deserve such Fan/PS airflow options?).

Wait....

Hi Vincent,

 

months have passed and I already know that, probably, the answer you gave me was (and still it is) definitive...nevertheless looking at Edgecore offering (note the blue Fans B2F):

 

 

I still don't understand why Aruba wasn't able to provide Back-to-Front (Power-to-Port) Power Supply modules and Fans for its Aruba 8320...it would be an appreciated addition especially for users that deployed Aruba 8320 in a Campus/DC IT room where the cold/hot air isles are well separated.  

Your comment has been forwarded to the Product manager.

Regards,

Hi Vincent Giles - and the rest of the community listening.

I also see inquiries from customers that want to change their 8320 hardware installation and desire (need) Power 2 Port or Back to Front cooling kit. Is there still no proper solution for this from Aruba or 3rd party ?


------------------------------
Tom Roholm
------------------------------

Original Message:
Sent: Jun 25, 2019 04:25 AM
From: Vincent Giles
Subject: Aruba 8320/8400X fans airflow direction

Your comment has been forwarded to the Product manager.

Regards,

Hi Tom, AFAIK (and I'm not an Aruba employee) and as of today (and after three years since the first discussion), a "solution" was not provided yet...it seems that Aruba decided to not consider the Back-to-Front ( = Power-to-Port) option as something to be commercialized (and engineered) for Aruba 8320 Switch Series...even if the EdgeCore (from which the 8320 was derived) has it since beginning.

------------------------------
Davide Poletto
------------------------------

Original Message:
Sent: Nov 10, 2021 10:43 AM
From: Tom Roholm
Subject: Aruba 8320/8400X fans airflow direction

Hi Vincent Giles - and the rest of the community listening.

I also see inquiries from customers that want to change their 8320 hardware installation and desire (need) Power 2 Port or Back to Front cooling kit. Is there still no proper solution for this from Aruba or 3rd party ?


------------------------------
Tom Roholm

Original Message:
Sent: Jun 25, 2019 04:25 AM
From: Vincent Giles
Subject: Aruba 8320/8400X fans airflow direction

Your comment has been forwarded to the Product manager.

Regards,

Hi Davide.

A pleasure to see you are as active as ever :-)

I agree that it does not seem like something we can get an Aruba SKU on, I wish so I supported solution could be acquired.

The 8360 10GBASE-T switch is about the same price tag as the 8320, but it would be nice to have a kit for customer with existing 8320 if the decide to change their physical installation, which is the case for my customer.


------------------------------
Tom Roholm
------------------------------

Original Message:
Sent: Nov 11, 2021 06:48 AM
From: Davide Poletto
Subject: Aruba 8320/8400X fans airflow direction

Hi Tom, AFAIK (and I'm not an Aruba employee) and as of today (and after three years since the first discussion), a "solution" was not provided yet...it seems that Aruba decided to not consider the Back-to-Front ( = Power-to-Port) option as something to be commercialized (and engineered) for Aruba 8320 Switch Series...even if the EdgeCore (from which the 8320 was derived) has it since beginning.

------------------------------
Davide Poletto

Original Message:
Sent: Nov 10, 2021 10:43 AM
From: Tom Roholm
Subject: Aruba 8320/8400X fans airflow direction

Hi Vincent Giles - and the rest of the community listening.

I also see inquiries from customers that want to change their 8320 hardware installation and desire (need) Power 2 Port or Back to Front cooling kit. Is there still no proper solution for this from Aruba or 3rd party ?


------------------------------
Tom Roholm

Original Message:
Sent: Jun 25, 2019 04:25 AM
From: Vincent Giles
Subject: Aruba 8320/8400X fans airflow direction

Your comment has been forwarded to the Product manager.

Regards,

Hi Tom, thanks!

"The 8360 10GBASE-T switch is about the same price tag as the 8320, but it would be nice to have a kit for customer with existing 8320 if the decide to change their physical installation, which is the case for my customer."

Don't say that too loud to me...it's more than three years that our VSX expels warm air from its back side and that flux mixes with the fresh air flux moving from the ground floor, the resulting unwanted warmer air flux is then available at the input of a very expensive storage! unfortunately I wasn't able to reverse the Aruba 8320 chassis due to issues with cabling length...not my fault here (we were forced to install the Aruba 8320 chassis that way...nobody thought it was impossible to exchange the PS/Fan kits from Red to Blue at a later time...so both switches are still running that way...luckily without problems).

With our new 8360 VSX that "error" was not repeated and it's really a pity the Aruba 8320 hasn't a Back-to-Front options since it is a very good switch with a very good ports density (and despite it is driven by a merchant silicon).

------------------------------
Davide Poletto
------------------------------

Original Message:
Sent: Nov 11, 2021 07:14 AM
From: Tom Roholm
Subject: Aruba 8320/8400X fans airflow direction

Hi Davide.

A pleasure to see you are as active as ever :-)

I agree that it does not seem like something we can get an Aruba SKU on, I wish so I supported solution could be acquired.

The 8360 10GBASE-T switch is about the same price tag as the 8320, but it would be nice to have a kit for customer with existing 8320 if the decide to change their physical installation, which is the case for my customer.


------------------------------
Tom Roholm

Original Message:
Sent: Nov 11, 2021 06:48 AM
From: Davide Poletto
Subject: Aruba 8320/8400X fans airflow direction

Hi Tom, AFAIK (and I'm not an Aruba employee) and as of today (and after three years since the first discussion), a "solution" was not provided yet...it seems that Aruba decided to not consider the Back-to-Front ( = Power-to-Port) option as something to be commercialized (and engineered) for Aruba 8320 Switch Series...even if the EdgeCore (from which the 8320 was derived) has it since beginning.

------------------------------
Davide Poletto

Original Message:
Sent: Nov 10, 2021 10:43 AM
From: Tom Roholm
Subject: Aruba 8320/8400X fans airflow direction

Hi Vincent Giles - and the rest of the community listening.

I also see inquiries from customers that want to change their 8320 hardware installation and desire (need) Power 2 Port or Back to Front cooling kit. Is there still no proper solution for this from Aruba or 3rd party ?


------------------------------
Tom Roholm

Original Message:
Sent: Jun 25, 2019 04:25 AM
From: Vincent Giles
Subject: Aruba 8320/8400X fans airflow direction

Your comment has been forwarded to the Product manager.

Regards,