where do you place the NAS on the rack

[benoitc]

I am curious whzere you place the rack mounted NAS on a rack, Someone told me recently that it was better to put them first at the bottom instead of starting them from the middle for their weight. It makes sense somehow but I'm curious what you are doing

 

[fredbert]

If it's a normal data centre rack I'd stick it where it's best. Given that you'd normally leave gaps between kit then it shouldn't matter where it is placed. Though if the device is particularly heavy you may want to consider your back (or head).

 

[Shadow]

Someone told me recently that it was better to put them first at the bottom instead of starting them from the middle for their weight.

That's a weird one and doesn't make sense to me. If it's at the bottem, it's still 'hanging' on the mount points. So nothing is gained from this. Plus, you should consider that they design their 19-inch racks to be strong enough to support their own weight. There are even rack-mountable 19-inch UPS'es that you can purchase, and boy I can tell you: THEY ARE HEAVY......!

 

[benoitc]

well these are 2-posts are racks , so the nas is not on a rail. We wanted to replace by a 4-post rack but we didn't find one that is not too deep (we wanted max 40-45 cm deep) and not too high (max 9u). These are common in some offices.

Also yes but gravity count so the less high you are the less force you will have somehow in such situation. That's probably the reasoning

 

[fredbert]

Was going to redirect you to another thread about two-post racks, but saw you started it

If you know someone with welding gear you could strengthen up a less stable rack?

 

[benoitc]

f you know someone with welding gear you could strengthen up a less stable rack?

i think what worries me is the rack slope. That why I think they were adivising to put heavy hardware at the bottom. Otherwise for now I am using Open-Frame Server Rack - 12U | Server Racks | StarTech.com

 

[Shadow]

Also yes but gravity count so the less high you are the less force you will have somehow in such situation. That's probably the reasoning

I better talk to the board of directors then for the company I work for. In one of our offices we have our datacentre on the 12th floor. Better convince them we need money to move the DC to the ground floor... :s

 

[benoitc]

I better talk to the board of directors then for the company I work for. In one of our offices we have our datacentre on the 12th floor. Better convince them we need money to move the DC to the ground floor... :s

i meant high in the rack the office ois in an old house at the last story there (because all wires are arial...)

 

[jeyare]

I am curious whzere you place the rack mounted NAS on a rack, Someone told me recently that it was better to put them first at the bottom instead of starting them from the middle for their weight. It makes sense somehow but I'm curious what you are doing

it was me in this thread, but it wasn’t about bottom or middle position, it was about: you need purchase proper rack type, then you can mount anywhere.
Bur anywhere is also unclear:
- for open rack, anywhere is valid, still need thinking about airflow (half U)
- for enclosed rack w/o active cooling, also need thinking about the airflow, also for thermal flow from other devices in the rack (what will bake another)
- for enclosed rack with active cooling, you don’t care

 

[NSquirrel]

C of g; air flow, including any other sources of heat beneath the NAS; fixed or moveable rack; also whether closed or open frame; if enclosed are fans needed for airflow; cables connections, both mains and data cables, for both routing and access; maintenance access...

Many of the above will depend on location. (A lot of years spent fitting test sytems and equipment into racks in all sorts of different situations.)

 

[jeyare]

Frequent mistakes, when people start considering about purchase of rack for home usage (from top to lowest):

1. Price as one and only measurement factor.
When the rack architecture, features, ... are responsible for proper operation conditions for your devices as:
a) robust for existing and planed devices (deflection)
b) sufficient internal capacity for existing and planed devices (managed/static thermal airflow)
c) side access for clean cable management or future maintenance of any devices or future airflow management upgrade
d) ...
then the price must be last (important) factor. Because purchase of cheap and nice rack can be useless for proper operation of your devices, e.g. too warm operation that will decrease lifespan of entire device or parts (HDDs, CPUs, ...).
Then paper and pencil is your better friends as hurry to purchase.

2. Robust
You can find many of rack solutions. Some of them are usable just for light weight devices, e.g. retail router and small switch or small NAS. Then you need read carefully:
- shelf based rack for laying the devices on a shelf, when the mass is distributed trough whole shelf area (physics)
- rack mount based for light weight devices (check the rack weight capacity, but also use your brain, because the physics will catch you, or seller behavior). Specific category is two posts rack (threat to problem with them)
- rack mount based for normal operation (check the rack weight capacity)
Then any nice (design first) rack can finally throw your investment to wastebasket, because can be useless for another important features.

3. Sufficient internal capacity for existing and planed devices
Heat is you enemy. You need take into consideration that each devices has a heat beaming not just from fan side, but from top, bottom, sides, front, back (up to design of the devices), touch it and you will feel it.
Then you need sufficient air capacity for the heat flow (airflow), up to the rack construction:
- in open rack, with no AC you need count with static airflow based on your room conditions (seasonable changed, summer by sun heat, winter by kind of heating e.g.). In this kind of rack you have to count with dust. More than in others. Dust is everywhere, even when your cleaning obsession is in high level. Dust will cover not just fan, but internal area of the devices (device case), which is primary used for cooling. Then the dust decrease the heat carrying from devices, then you decrease the devices lifespan. In such kind of racks you need count with space between devices, single U is minimum.
If you have such rack in AC room, it is better, but still need to think for hours, when your AC is switched off.
- cabinet based rack, same as above (more you can find in next paragraph). If you have AC room, then the space between the devices cane be narrower or zero }up to your average temperature in the room.
Recommendation:
frequent visual check and cleaning of dust from you devices is proper approach in this scenario.

3. Cabinet based rack
Plenty of them are available. I will just use main differences:
a) solid walls
b) mesh walls
When solid walls keeps your device covered against the dust, you need count with "blocked" airflow.
When mesh walls will provide better thermal carrying, you need count with more dust in the devices.
Glass doors is really bad idea for the thermal carrying. If you can change it to mesh doors, or purchase new custom glass with circle hole for big fans (slow rpm, better is managed rpm) do it. Don't forget for hole for fan attachment. It was my case, when custom build glass doors, then tempered for heavy resistance can help your airflow (silent managed fans from Noctua) and dust under control (dust filters). Not a huge investment, but result is perfect.
What is good idea is two fans (120mm, slow rpm, managed) inside in the cabinet (in 1/3 of height), that will give you controlled airflow to upper side of the rack, where two fans carrying heat out.
Then you need just management console with thermal sensors for right fans operation in the cabinet. My is NZXT Sentry LXE, purcahsed 5y ago, still in right operation.
Of course this setup is valid for 4 NASes, and USG Pro + Unifi 48p switch, include Fiber ONU in one of my site. I need change my exist rack next year to bigger, then I will chose Mesh walls (room is now AC).

4. Side access (or back)
This feature is frequently underestimated.
It can help you better organize your wires to maximize airflow w/o obstructions. A mess of cables is the another important objective of decreased heat carrying from the rack.
There is (my also) another objective:
- in future you can decide to purchase static/dynamic airflow management, then you will need to install fans and thermal sensors.
Finally it is better for any kind of maintenance or dust inspection/cleaning.

Of course we can speak about another points. But this is short recommendations related to home/SME operation.

 

[Rusty]

I can't wait to start working on my 42U... Got additional shelf and M6 screws today and stared to configure my 24port switch yesterday... Fun times ahead.

 

[jeyare]

I can't wait to start working on my 42U... Got additional shelf and M6 screws today and stared to configure my 24port switch yesterday... Fun times ahead.

Don’t forget for a shelf for smoked sausages

 

[Rusty]

Well ofc not! (got that one already... ofc fucking ofc)

 

[benoitc]

Frequent mistakes, when people start considering about purchase of rack for home usage (from top to lowest):

1. Price as one and only measurement factor.
When the rack architecture, features, ... are responsible for proper operation conditions for your devices as:
a) robust for existing and planed devices (deflection)
b) sufficient internal capacity for existing and planed devices (managed/static thermal airflow)
c) side access for clean cable management or future maintenance of any devices or future airflow management upgrade
d) ...
then the price must be last (important) factor. Because purchase of cheap and nice rack can be useless for proper operation of your devices, e.g. too warm operation that will decrease lifespan of entire device or parts (HDDs, CPUs, ...).
Then paper and pencil is your better friends as hurry to purchase.

2. Robust
You can find many of rack solutions. Some of them are usable just for light weight devices, e.g. retail router and small switch or small NAS. Then you need read carefully:
- shelf based rack for laying the devices on a shelf, when the mass is distributed trough whole shelf area (physics)
- rack mount based for light weight devices (check the rack weight capacity, but also use your brain, because the physics will catch you, or seller behavior). Specific category is two posts rack (threat to problem with them)
- rack mount based for normal operation (check the rack weight capacity)
Then any nice (design first) rack can finally throw your investment to wastebasket, because can be useless for another important features.

3. Sufficient internal capacity for existing and planed devices
Heat is you enemy. You need take into consideration that each devices has a heat beaming not just from fan side, but from top, bottom, sides, front, back (up to design of the devices), touch it and you will feel it.
Then you need sufficient air capacity for the heat flow (airflow), up to the rack construction:
- in open rack, with no AC you need count with static airflow based on your room conditions (seasonable changed, summer by sun heat, winter by kind of heating e.g.). In this kind of rack you have to count with dust. More than in others. Dust is everywhere, even when your cleaning obsession is in high level. Dust will cover not just fan, but internal area of the devices (device case), which is primary used for cooling. Then the dust decrease the heat carrying from devices, then you decrease the devices lifespan. In such kind of racks you need count with space between devices, single U is minimum.
If you have such rack in AC room, it is better, but still need to think for hours, when your AC is switched off.
- cabinet based rack, same as above (more you can find in next paragraph). If you have AC room, then the space between the devices cane be narrower or zero }up to your average temperature in the room.
Recommendation:
frequent visual check and cleaning of dust from you devices is proper approach in this scenario.

3. Cabinet based rack
Plenty of them are available. I will just use main differences:
a) solid walls
b) mesh walls
When solid walls keeps your device covered against the dust, you need count with "blocked" airflow.
When mesh walls will provide better thermal carrying, you need count with more dust in the devices.
Glass doors is really bad idea for the thermal carrying. If you can change it to mesh doors, or purchase new custom glass with circle hole for big fans (slow rpm, better is managed rpm) do it. Don't forget for hole for fan attachment. It was my case, when custom build glass doors, then tempered for heavy resistance can help your airflow (silent managed fans from Noctua) and dust under control (dust filters). Not a huge investment, but result is perfect.
What is good idea is two fans (120mm, slow rpm, managed) inside in the cabinet (in 1/3 of height), that will give you controlled airflow to upper side of the rack, where two fans carrying heat out.
Then you need just management console with thermal sensors for right fans operation in the cabinet. My is NZXT Sentry LXE, purcahsed 5y ago, still in right operation.
Of course this setup is valid for 4 NASes, and USG Pro + Unifi 48p switch, include Fiber ONU in one of my site. I need change my exist rack next year to bigger, then I will chose Mesh walls (room is now AC).

4. Side access (or back)
This feature is frequently underestimated.
It can help you better organize your wires to maximize airflow w/o obstructions. A mess of cables is the another important objective of decreased heat carrying from the rack.
There is (my also) another objective:
- in future you can decide to purchase static/dynamic airflow management, then you will need to install fans and thermal sensors.
Finally it is better for any kind of maintenance or dust inspection/cleaning.

Of course we can speak about another points. But this is short recommendations related to home/SME operation.

for me one of the factor was also the depth of the rack. i didn'find any 4U open frame < 50cm . but anyway i concur with all what you said. also having access to the back is a very good point.

 

[jeyare]

good luck

 

[fredbert]

For giggles, if all else fails, with a two-post rack you could try balancing the NAS on top of them

 

[benoitc]

For giggles, if all else fails, with a two-post rack you could try balancing the NAS on top of them

well the heavy duty 2-post from startech is good imo : Open-Frame Server Rack - 12U | Server Racks | StarTech.com

I mean if I find a 4-post rack that allows passive cooling with a configurable depth < 40-50cm I will take it

 

[jeyare]

just to be sure - depth of the mentioned Heavy duty 2-post rack is 30.6cm (follow product description)
take care about a balance of your 32.8 cm NAS deep
or use 15kg barbell disk to bottom as stabilizer of the rack balance

OFC, black one is better, in line with the rack collor

 

[fredbert]

OFC, black one is better, in line with the rack collor