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I can get some decent deals on eBay for rackmount servers (described as, for example, '2U rackmount server') that I'm looking at to replace my Synology NAS.

Would I be able to just buy this 2U server and sit it under my desk somewhere, or is it a requirement that you absolutely have to have a rack to put it in?

What does a rack give you that sitting it on its own somewhere does not?

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    People fairly commonly use lack coffee tables from ikea as a cheap 'rack'. I'd make sure it runs on whatever your household power is, since not all servers run on standard local voltages. – Journeyman Geek Mar 12 '15 at 7:15
  • I use my great-grandmother's dining room table as the rack for my rack server. Also, have you considered microservers OP? – NobleUplift Mar 13 '15 at 15:38
  • Why do you want to buy a rack mount server? A regular desktop computer will work just fine! – JeremiahBarrar Mar 17 '15 at 13:27
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You don't necessarily need a rack or cabinet. Some points to keep in mind though:

  • If you keep it under your desk it will accumulate dust.
  • The fans of such servers can be rather loud (edit: put mildly! You really don't want that near you all the time!)
  • The power consumption might be much higher than that of a SOHO NAS box.
  • Rackmountable servers come 19" wide and might be twice that in length.
  • If you get an old server with parallel SCSI (not SAS) you will not be able to easily put in SATA-HDDs for regular SOHO-NAS Systems.
  • Upgrading parts might be more difficult since they use server hardware (RAM, CPU, HDD etc).

A rack has the advantage that you can mount more than 10 servers in a single rack easily and if you have them on rails still be able to access them (slide out, open up, swap parts etc.). Also cable management, airflow management and power distribution come to mind.

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    "The fans of such servers can be rather loud" Since we're understating things today, I hear the Nazis were "kinda mean". :-p – ceejayoz Mar 11 '15 at 21:12
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    Rather loud... That's putting it mildly... Think jet-fighter on take-off with full afterburner. In an office environment it is that kind of loud. – Tonny Mar 11 '15 at 21:43
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    Okay, point taken. Better (see edit)? :-) – TheUser1024 Mar 11 '15 at 22:32
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    This video demonstrates the noise you can expect from these things, and even then the video feels kinda quiet to what you'd get in reality. – user256743 Mar 12 '15 at 3:13
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    Also rackmount servers are built with a cleaner environment in mind, they will clog up with dust and overheat far more easily than a tower based server. – JamesRyan Mar 12 '15 at 16:55
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Basically, rack is just a... a rack. Just a metal construction to put hardware in some compact and standardized manner. It may have walls and doors, power distribution units, cable organizers, coolers and other stuff, and may not.

So, the rack is not mandatory to place rackmount hardware. Feel free to put your server anywhere you want (but not to the place where you'll not put any other computer).

Servers, of course, have their own cooling systems. Keep in mind that 1U and 2U cases often have very noisy coolers, and it's not very good decision to put them near your workplace.

16

A rackmount server need not be physically installed in a rack, but there are several important considerations when operating one at home.

  • As far as I can tell, there is no regulatory or other requirement for a rackmount server to be installed in a rack. I've seen rackmount servers operated on a table at my college.

  • As others have noted, thermals can be an issue, so be sure to provide plenty of ventilation in front of and behind the system case. Cool air is taken in from the front and hot air is expelled from the back.

  • Rackmount servers also tend to have very noisy fans, especially compact 1U models which need to move lots of air within a constrained chassis. I've experienced it firsthand and know how loud these things get. You do not want to be sitting near them.

    • For comparison with a consumer part, a rackmount server running under a moderate load with good ventilation is typically at least as loud as a reference AMD Radeon R9 290X graphics card with the fan running at 100%, which is about 65 dBA. Expect even more noise under suboptimal operating conditions, potentially up to 75–80 dBA. Many older models may not have automatic fan speed control at all and therefore always operate at the maximum noise level.

Rackmount servers are ultimately not designed for home use.

  • You should bear in mind that by their very nature, rackmount servers are not designed to be operated in any sort of residential setting. In fact, some rackmount servers may be illegal to sell for use in a home environment (at least in the United States) because they are FCC Class A devices and emit too much electromagnetic radiation, to the point where harmful interference to electronics may result (emphasis added):

    Server and Switch Information - This device has not been approved by the Federal Communications Commission for use in a residential environment. This device is not, and may not be, offered for sale or lease, or sold or leased for use in a residential environment until the approval of the FCC has been obtained. Source


    FCC, Class A

    This product has been tested and found to comply with the limits for a Class A digital device pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This product generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the manufacturer’s instruction manual, may cause harmful interference with radio communications. Operation of this product in a residential area is likely to cause harmful interference, in which case you will be required to correct the interference at your own expense. Source

  • A more appropriate solution is a tower case with multiple hot-swap bays. These cases are designed for use in a SOHO environment, and make a lot more sense than a rackmount server if you're trying to build a storage server for home use.

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    ..In fact, some rackmount servers may be illegal to sell for use in a home environment (at least in the United States).. Do you have any references to support this? – MDMoore313 Mar 13 '15 at 13:39
  • @BigHomie: See edit. – bwDraco Mar 13 '15 at 13:54
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If what you're looking for is a way to avoid buying an expensive rack, you might be able to make do with a (stack of) IKEA LACK tables.

This might be the "most official" site about it: https://wiki.eth0.nl/index.php/LackRack

Edit: I see someone else already suggested this.

5

You should also be aware of cooling of the rack mounted server. Rack mounted servers expect cool air in the front and be able to exhaust hot air from the back of the machine. They aren't going to be as efficient in cooling if there is no hot/cold aisle separation. Let me explain what a hot/cold aisle is. Most data centers have cold air chillers force cold air in the front and then have the chiller intakes (the hot air) in the back. That way there is no heat build up in the front of the machine thereby giving it nice steady steam of cool air. That said, since they have small jet engines for fans, they should be OK in an office setting.

  • Should be? Or should not be? – Kate Gregory Mar 13 '15 at 11:54
  • Should be OK as long as it doesn't get too much hot air in the front. Additionally, most servers have temperature sensors that you can access via the network. – BigD Mar 13 '15 at 16:20
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The primary purpose of a rack is server density. In a data center, racks/cabinets provide a way to "stack" machines without actually putting the weight of each machine on the ones beneath it. This is why all rack-mount servers have screw holes in the sides - rails are attached to them and slide into the cabinet, supporting the weight of the machine. The thumb screws on the front of the machine simply secure it to the rack to prevent accidental sliding. Some cabinets have cooling fans built in to circulate the air, but this is mostly due to the density achieved by the rack.

To answer your question, you don't need to mount a rack-mountable server. It can live happily on or under a desk, as long as it has adequate clearance for ventilation.

3

And this is more anecdotal instead of giving you studies or data... I have managed several small to medium sized labs (30-80 servers) for direct exchange feeds in the dev, QA, and training departments. We have had high end servers stacked on top of each other up to 20U high. Normally we stop at 6-8U but we have had the old 385's that were 4U stacked 5 high. We did have racks available but that seemed like too much work when we would possibly configure 8 servers in a day and send them to client site or another center. This lasted 10+ years and never a non-rack related issue other than, "Hey dude pick up the first 4 servers so I can take the 2nd one out." The stack height at your lab should be in proportion to the muscle you have available (no offense to my 130 pound chain smoking ex-coworker who would start tilting over with one 385).

3

At home (in my "man cave") I have two Ikea Lack tables, stacked one on top of another. The lower Lack has the shelf installed with two 1U servers installed. My MicroServers are sat on the top of the first table, with a switch next to it, and then a KVM switch, mouse, keyboard, and screen on the top of the second table. The shelf from the second table is placed on top of the first one to reinforce it.

For my purpose, this works well. However, due to the noise of the servers and the power draw I only run them when no-one else is home and only for a few hours a month (when I'm actually using them.

For a cheap solution, it's not a bad idea. Even better if you can put them somewhere out of the way like under the stairs or in a basement.

protected by slhck Mar 13 '15 at 14:46

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