Identification of two round holes on top of rack.

[Spork Schivago]

Hello!

I've searched the internet, skimmed through a lot of HPE PDFs, all searching for the answer to a simple question. On the top of my HPE H6J77A Advanced Series rack (36U), there are two round holes on the front top of the rack. What are those holes for?

Here is a picture of the holes that I'm talking about. I know what the square on the back is for.

I originally thought fans, but no, the fan kit is for the middle of the top of the rack. Then I thought maybe duct work for cooling, but that doesn't make sense with both being on the top there. I looked through the Options manual for the rack, which shows how to install all the various add-on's that go into the rack or that are available for the rack, and there's nothing on those two holes.

Any ideas?

**EDIT: Never mind. I found it on a technical datasheet. ROOF CABLE ACCESS FRONT LOCATION. I just have to figure out how to pop them out now. Thanks!

[stj]

Re: Identification of two round holes on top of rack.

whats on the base?
2 big round feet by any chance?

[petehall347]

Re: Identification of two round holes on top of rack.

maybe dust catchers .would depend on air flow .

[Spork Schivago]

Re: Identification of two round holes on top of rack.

whats on the base?
2 big round feet by any chance?

The base of the rack? It's mostly open, minus directly underneath where those circles are. There's a metal bar that goes across. On each side of the bar, there's a cutout L and two very small holes cut out.

Those two holes at the top, according to the technical datasheet for the rack, are for running cables to the front of the rack.

With our current setup, most of the cables are ran to the rear. We have coax that will be ran to the front and cat 5e plenum rated ethernet that will be ran to the front, for telephone.

We're currently using a POTS type telephone system. Eventually, we'll switch to VoIP. I plan on using a CAT 6 UTP patch panel I got for the telephone. I'll daisy chain all 48 ports together. Then plug in the incoming telephone line into port 1 or something, and all the other lines will be output.

That's the only way I could figure to wire up the phone system with what I had. I think they make IDC 66 blocks or something for telephone, but I had the CAT 6 patch panel lying around and figured I could make it work, at least until we get VoIP services.

[Spork Schivago]

Re: Identification of two round holes on top of rack.

maybe dust catchers .would depend on air flow .

I'm a bit concerned about temperatures. I have sides for the rack and I will be installing them once everything's configured. They make some sort of air kit for the rack, where it seals all the gaps. I am trying to figure out a way to cool the datacenter.

I have 5 or 6 small windows in the room. I was thinking even once we get central air next year, I'll probably have to install a few smaller ACs. Maybe 5,000 BTU. I'm going to have to look at the datasheets for all the various equipment and see if I can find out how much heat they're generating.

Most of the equipment is HPE and they're pretty good about listing that in the datasheets somewheres. I think I can just total the heat dissipation in BTUs and whatever I end up with, just buy ACs that total that amount.

They do make a rack that has some duct work installed on it. From what I was reading (I didn't look into it that much), it's just got something that hooks up to the cold air return.

I see they also make racks that got built-in coolers, but they're pricey! The price for the HPE one was something like 33,000$! It looks like it's got an AC the height of the rack attached to the side. It's got some glass (maybe plexiglass, I dunno) for the door, with the regular door after that, that keeps the air from escaping.

[stj]

Re: Identification of two round holes on top of rack.

your in the basement, isnt there ducting for a tumble dryer or a furnace??

[Spork Schivago]

Re: Identification of two round holes on top of rack.

your in the basement, isnt there ducting for a tumble dryer or a furnace??

The furnace and hot water tank are both direct vent. 3" PVC or something small like that and it vents directly outside.

The dryer vents up to the ceiling area and then goes outside. It's one of those metallic dryer vents.

What are you thinking Stj? Because of the way the basement was modified (not by me), the floor is not level at all. The rack cannot be moved to many areas because it hits the ceiling.

Originally, I thought I could hook up duct work to one of those holes and hook that to some sort of air conditioner. I think now though, it'd be best to run the coax through one hole, the ethernet for the telephone through the other hole, and the CAT6 for data through the back.

[stj]

Re: Identification of two round holes on top of rack.

i'm thinking put a fan-rack in the lowest or highest bay - they are almost free at equipment auctions.
and duct the hot air from the top into your existing ducting.

[Spork Schivago]

Re: Identification of two round holes on top of rack.

i'm thinking put a fan-rack in the lowest or highest bay - they are almost free at equipment auctions.
and duct the hot air from the top into your existing ducting.

In the picture in the first post, it's very similar to my rack, but not my rack. You see four little holes in that pic. In my rack, between the front two holes that I was asking about, and the rectangle brush access in the back, there's a giant rectangle plate.

I removed that plate and added the fan kit. It's six high powered fans. They're very loud but I think once I add the sides, it'll keep air flowing through the case.

The fan kit is a 220V fan kit. I can take a picture if you'd like.

[stj]

Re: Identification of two round holes on top of rack.

sounds similar to the ones i used to buy - i used to buy ones that fitted in the first or last position with 6 or 9 120mm mains fans.

i used to get them at auctions for about £5 and just strip them for the fans!

[Spork Schivago]

Re: Identification of two round holes on top of rack.

sounds similar to the ones i used to buy - i used to buy ones that fitted in the first or last position with 6 or 9 120mm mains fans.

i used to get them at auctions for about £5 and just strip them for the fans!

These fans don't actually go in any of the rack positions. You remove a square filler plate on the very top of the rack (between the brushed square hole and the two round circular holes), then you install the fan system, screw it down, ground it, run the power.

With the sides off, I don't think it'll do much. I'm hoping with all the cables in there, it'll help with the air flow a bit. With the devices where I can choose the air flow direction, I blow it from front to back, so hot air is coming out the the rear of the rack.

Now I gotta buy some VDA licenses but I'm not 100% sure if I've been given the correct info. The way I understand it, we use our Microsoft 365 E3 licenses to install Windows 10 Enterprise E3 in a VM (one user based license allows 5 installs of Windows 10 Enterprise E3 and 5 installs of Office on a PC and 5 installs on cell phones). Then we license the connecting devices with VDA.

For example, I will be using one of the laptops to connect to the VMs, so the laptop would need a VDA license, not the VMs. Same with the workstation.

The way I read it, even the Linux systems would need a VDA license if they were interacting with the VMs running Windows, unless I'm the primary owner of the VDA license and it's my Linux box, then it's covered under their roaming rights.