File Server vs external drive 20 ft (6 meters) away

Silencing hard drives, optical drives and other storage devices

Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee

Post Reply
nomoon
Posts: 210
Joined: Thu Apr 14, 2005 8:35 pm
Location: Allen, TX US
Contact:

File Server vs external drive 20 ft (6 meters) away

Post by nomoon » Mon Feb 04, 2008 12:50 pm

I would like to have a remote drive location about 20 ft (6 meters) from my desk for storing almost 1 TB of data for back ups and extra storage. This is too far to use E-SATA. I'm planning to place it a closet in the next room. I'm planning to start with a single 1 TB drive, and will likely add another in the future.

I have an old Dell XPS 450 MHz machine running Win2K that I could use to run the hard drives. I would have to install a SATA card since the MB only supports PATA. I would also install a 1 Gb ethernet card. The machine isnt' terribly quiet compared to my custom P180 machine, so I'd definitely want to run it in the next room. Does anyone know of a reason why this might be a bad idea or wouldn't work?

Another alternative is to use a stand alone drive box using ethernet, or something like high speed USB or Firewire. Ethernet cables are cheap, while USB and Firewire aren't.

Any wisdom that anyone can share would be appreciated. Thanks in advance!

Jason

Strid
Posts: 397
Joined: Tue Jan 08, 2008 5:09 am
Location: Copenhagen, Denmark

Post by Strid » Mon Feb 04, 2008 1:12 pm

There is a dealer in Denmark that sells a 10 m Firewire cable for roughly $30. Why not just use a long Firewire/USB2.0 cable, they're not very expensive. You might actually save money, when you factor in the cost of running an outdated PC just for the storage. My vote for USB/Firewire1 :D I bet that you don't need to spend more than $40 tops on a cable.

awolfe63
Posts: 29
Joined: Sat Oct 27, 2007 3:25 pm

Post by awolfe63 » Mon Feb 04, 2008 1:12 pm

Supposedly - the new wireless USB will do 30'

seraphyn
Posts: 322
Joined: Wed Nov 28, 2007 1:26 pm
Location: Netherlands

Post by seraphyn » Mon Feb 04, 2008 1:16 pm

I have a 1,5TB fileserver in a closet across from my room, gotta say it works great. No noise, no hassle and since i have the fileserver on 24/7 anyway i also use it as my download box so i can turn off my PC at night.

Strid
Posts: 397
Joined: Tue Jan 08, 2008 5:09 am
Location: Copenhagen, Denmark

Post by Strid » Mon Feb 04, 2008 1:28 pm

By the way, how many megabytes/second can you get from a USB2.0 or FireWire connection? The OP has a really great idea. I only use my 2nd drive to store various stuff on. Migh aswell put it away completely!

zprst
Posts: 15
Joined: Tue Aug 15, 2006 3:56 pm

Post by zprst » Mon Feb 04, 2008 2:28 pm

maximum theoretical bandwidth of USB 2 is 480Mbit/s, firewire (ieee1394 aka firewire 400) - 400Mbit/s, thus somewhat limiting the maximum throughput of modern SATA disks.

personally, I'm using the 'old machine in the closet', which works nice for me, mainly because it's not only used for storage, but also differend kinds of small tasks requiring 24/7 operation. Using such system just for storage needs may be convinient sometimes, but in most cases that probably would be a huge overkill, maintainance-wise and power consumption-wise (my system, a 500Mhz mendocino-core celeron on an intel BX mainboard w. 2 samsung HA250JC drives is typically using between 40 and 55 watts)

you should also keep in mind that using a gigabit ethernet card would nearly starve the (32bit 33Mhz, I assume) PCI bus, which is a really bad thing if you're using gigabit ethernet to transfer data to a storage subsystem sharing the same PCI bus (you've mentioned a PCI SATA controller)...
max. PCI bandwidth: ~1066 Mbit/s
max. GbE bandwidth: ~1024 Mbit/s
max. throughput of a modern SATA drive: over 800 Mbit/s, max. *theoretical* bandwidth for a connection between drive cache and controller reaching up to 3Gb/s (sata II)

using a USB or firewire enclosure could also pose a problem - none of them would officially support required cable length:
The maximum length of a standard USB cable is 5.0 meters (16.4 ft). The primary reason for this limit is the maximum allowed round-trip delay of about 1500 ns. If a USB device does not answer to host commands within the allowed time, the host considers the command to be lost. When USB device response time, delays from using the maximum number of hubs and delays from cables connecting the hubs, host and device are summed, the maximum delay caused by a single cable turns out to be 26 ns [9]. The USB 2.0 specification states that the cable delay must be less than 5.2 ns per meter, which means that maximum length USB cable is 5 meters long. However, this is also very close to the maximum possible length when using a standard copper cable.

Using USB devices over a greater length require hubs or active extension cables. Active extension cables are bus-powered hubs equipped with two maximum length standard USB cables. USB connections can be extended to 50 m (160 ft) over CAT5 or up to 10 km (6.2 mi) over fiber by using special USB extender products developed by various manufacturers.

In practice, some USB devices may work with longer cable runs than 5 meters, if the number of hubs between the host and the device is less than the maximum number allowed by the USB standard. However, using a longer cable lowers both the signal quality and the voltage provided by the USB bus below the specification tolerance limits. This may prevent USB devices from working properly or even from working at all.
Cable length is limited to 4.5 metres (14.8 ft), although up to 16 cables can be daisy chained using active repeaters, external hubs, or internal hubs often present in FireWire equipment. The S400 standard limits any configuration's maximum cable length to 72 meters.
(quotes from corresponding wikipedia articles)

maybe a simple 1-drive NAS box (like one of those buffalo linkstations, for example) with gigabit ethernet network adaptor is what you are looking for? best of both worlds -- versatile ethernet cabling, low fuss, easy setup and relatively low power usage.

nomoon
Posts: 210
Joined: Thu Apr 14, 2005 8:35 pm
Location: Allen, TX US
Contact:

Post by nomoon » Mon Feb 04, 2008 5:33 pm

Thanks for the info. It seems that if I'm going 20 feet (~6 meters), then none of my cabling options will be as fast as the drive (3 Gb/sec). I understand that a 1 Gb ethernet cable will only be able to transmit about half that bandwidth as data bandwidth to the drive, which would be comparable to USB 2 (480Mbit/s) or firewire (ieee1394 aka firewire 400) - 400Mbit/. It won't matter whether the ethernet is starving the PCI bus. I was concerned that the PCI bus might be a bottleneck on the machine.

For the initial drive, it might be cheaper to run USB or Firewire cables. However, for subsequent drives, it looks like it would be cheaper to use the server solution, since all I would have to do would be to purchase additional drives.

I'll look into the Buffalo boxes. Thanks!

Spare Tire
Posts: 286
Joined: Sat Dec 09, 2006 9:45 pm
Location: Montréal, Canada

Post by Spare Tire » Mon Feb 04, 2008 5:46 pm

seraphyn wrote:I have a 1,5TB fileserver in a closet across from my room, gotta say it works great. No noise, no hassle and since i have the fileserver on 24/7 anyway i also use it as my download box so i can turn off my PC at night.
How do you make the download box? Can you manage it remotely?

seraphyn
Posts: 322
Joined: Wed Nov 28, 2007 1:26 pm
Location: Netherlands

Post by seraphyn » Tue Feb 05, 2008 12:43 am

The download box is basically a seperate harddrive on the fileserver for downloading purposes to which any and all download programs dump their data.
I use RealVNC for remote managing. If you use a windows server and a windows client however, i would suggest using the built in Remote Desktop Connection (Start-Programs-Accessories-Communications) since it will work faster.

CoolGav
Posts: 398
Joined: Wed Jul 23, 2003 4:26 am
Location: €ngland
Contact:

Post by CoolGav » Tue Feb 05, 2008 8:56 am

zprst wrote:you should also keep in mind that using a gigabit ethernet card would nearly starve the (32bit 33Mhz, I assume) PCI bus
The older PIII of nomoon's would have 33MHz PCI, so this would be an issue. However more modern motherboards with PCI2.2 and later will be able to run at 66MHz if all PCI cards support it. My own server (I've just found out) does this - I have on the same PCI bus a gigabit card and an IDE controller, both capable of 66MHz, which doubles the bandwidth and means performance is OK.

The PIII wont take too much power, although you could use a newer PSU (if it isn't a Dell non-standard one) for better efficiency. I have a PIII that I use for backups which doesn't need much power (but is terrible for F@H).

If you run Linux on the server then it's easy (if you've ever done any *NIX) to get other services up and running like Email, FTP, web, and have loads of automated stuff.

michaelb
Posts: 53
Joined: Mon Nov 03, 2003 3:35 pm
Location: Texas

Post by michaelb » Tue Feb 05, 2008 1:41 pm

If USB is fast enough for what's to be stored on the drives, and only one PC needs to access them, then that would seem to me the cheapest and probably best option.

Hard drives are often cheaper when you buy them as an external drive already in a USB enclosure. So, just wait for a good deal on a 1TB USB drive.

USB cables and hubs are pretty cheap if you look around. For the first drive, just get two long USB cables, and a hub between them. When you add a second drive, you could add another hub at the end of the cable, and use the short cables that come with the drives to connect both of them into the hub. Same for additional drives til hub is full.

jessekopelman
Posts: 1406
Joined: Tue Feb 13, 2007 7:28 pm
Location: USA

Post by jessekopelman » Tue Feb 05, 2008 3:29 pm

nomoon wrote:Thanks for the info. It seems that if I'm going 20 feet (~6 meters), then none of my cabling options will be as fast as the drive (3 Gb/sec). I understand that a 1 Gb ethernet cable will only be able to transmit about half that bandwidth as data bandwidth to the drive, which would be comparable to USB 2 (480Mbit/s) or firewire (ieee1394 aka firewire 400) - 400Mbit/. It won't matter whether the ethernet is starving the PCI bus. I was concerned that the PCI bus might be a bottleneck on the machine.
SATA bus speed might be 3 Gbps, but there are no single drives capable of putting out > 1 Gpbs of real throughput. The only reason you should care about speeds > 1 Gbps are if you are going to use an array of drives. Also, 20" Cat5e or Cat6 cable is perfectly capable of supporting 1 Gbps in each direction (or both simultaneously, for that matter). The PCI card or PCI bus itself will be the limiting factor, not the cable. As for USB 2, the theoretical speed is 480 Mbps, but the real speed for HDD applications is never > 300 Mbps. Firewire, on the other hand gets very close to its rating of 400 Mbps (ie Firewire 400 is faster than USB 2 for this application). There is also such a thing as Firewire 800.

aspirina750
Posts: 7
Joined: Mon Jan 28, 2008 1:00 pm
Location: Barcelona

Post by aspirina750 » Tue Feb 05, 2008 5:42 pm

I´m using this at home, it works really well and it´s fairly cheap.
http://netgear.com/Products/Storage/Net ... C101T.aspx

The transfer rates are very good and I can share the drives via wi-fi or cable with the other computers at home.

scdr
Posts: 336
Joined: Thu Oct 21, 2004 4:49 pm
Location: Upper left hand corner, USA

Post by scdr » Tue Feb 05, 2008 8:28 pm

You might also want to figure power into your cost considerations.

How will you turn it off when it isn't needed/active?
And turn it on when it is?

For a remote PC - you can probably shut it down remotely (or based on time/etc.) via software
use wake on LAN (or timer) to turn it on when needed.

For a remote USB/firewire drive - can use X-10 controller (or a long extension cord) to turn off when not in use.

(If you leave it on all the time - will add to cost (e.g. 40w idle PC left on 24/7 is about $40/year at current average US electricity rates. May be much more in some areas.)

nomoon
Posts: 210
Joined: Thu Apr 14, 2005 8:35 pm
Location: Allen, TX US
Contact:

Post by nomoon » Tue Feb 05, 2008 8:52 pm

For the Netgear or the Buffulo networked box, is it possible to install two independent hard drives, or do they need to be RAID'ed together into one big drive? I've seen a few multidrive external boxes, but the specifications seem to imply that the drives must be combined in a RAID configuration.

michaelb
Posts: 53
Joined: Mon Nov 03, 2003 3:35 pm
Location: Texas

Post by michaelb » Wed Feb 06, 2008 1:14 pm

scdr wrote:e.g. 40w idle PC left on 24/7 is about $40/year at current average US electricity rates. May be much more in some areas.
OP is in Texas... in Winter, will probably replace some electric heating, but in Summer... wouldn't surprise me if takes at least an extra 100 watts of A/C to counteract the 40 of heat generated.

scdr
Posts: 336
Joined: Thu Oct 21, 2004 4:49 pm
Location: Upper left hand corner, USA

Post by scdr » Wed Feb 06, 2008 2:13 pm

michaelb wrote:
scdr wrote:e.g. 40w idle PC left on 24/7 is about $40/year at current average US electricity rates. May be much more in some areas.
OP is in Texas... in Winter, will probably replace some electric heating, but in Summer... wouldn't surprise me if takes at least an extra 100 watts of A/C to counteract the 40 of heat generated.
Will help heat in winter, though unless it is used to heat a small area (in lieu of central heating a much larger area), electric heat is relatively inefficient.
(Heat is generally converted to electricity, run down the wires (line loss), then turned back into heat.)

The other day I was curious about how much extra A/C load a watt of heating takes. A little searching (e.g. Wikipedia on air conditioning) suggests that well maintained recent A/C units take about 1 Watt of power to remove 3 watts of heat. (i.e. an extra 40 watt heater = extra 13 watts AC). (Older A/C likely less efficient.)

But neither of these observations based on solid references/research. Anybody have good reference on either of those topics?
(relative heating efficiency of different energy delivery methods,
or how much extra power takes to cool an added heat load).

So turning it off when not in use still most efficient.

michaelb
Posts: 53
Joined: Mon Nov 03, 2003 3:35 pm
Location: Texas

Post by michaelb » Thu Feb 07, 2008 7:54 am

That's surprising. If at all close to accurate, then costs of leaving equipment on are much lower than I thought. Many in the South use electric heating, so costs in Winter may already be low.

Efficiency is given in SEER or EER for models I found with quick search.

I don't follow what you mean about conversion of heat to electricity. I would have guessed that a 40 watt PC left always on would be similar to a 40 watt electric heater, or an old 40 watt light bulb in a room without windows.

scdr
Posts: 336
Joined: Thu Oct 21, 2004 4:49 pm
Location: Upper left hand corner, USA

Post by scdr » Thu Feb 07, 2008 1:11 pm

I don't follow what you mean about conversion of heat to electricity. I would have guessed that a 40 watt PC left always on would be similar to a 40 watt electric heater, or an old 40 watt light bulb in a room without windows.
As you say, almost all the energy used by a computer winds up as heat, and heat is heat - doesn't matter if comes from electric light bulb, electric heater, a person.

My figures come from the following (based on very superficial research (i.e. what comes up quick in google and wikipedia ;-) - if anybody knows anything about this or has some good reference, please leap in and correct or confirm this):

Wikipedia entry on air conditioners:
"As an example presume that inside the closed system a 100 watt light bulb is activated, and the air conditioner has an efficiency of 200%. The air conditioner's energy consumption will increase by 50 watts to compensate for this, thus making the 100 W light bulb utilise a total of 150 W of energy.

Note that it is typical for air conditioners to operate at 'efficiencies' of significantly greater than 100%, see Coefficient of performance."


"However, modern [portable AC] units run on approximately 1 to 3 ratio i.e., to produce 3 kW of cooling this will use 1 kW of electricity."
From figures below, this appears to relate to more efficient current units,
older units were generally less efficient, and even typical current units may be less efficient. Doing a little extra looking turned up:
"Today's best air conditioners use 30% to 50% less energy to produce the same amount of cooling as air conditioners made in the mid 1970s. Even if your air conditioner is only 10 years old, you may save 20% to 40% of your cooling energy costs by replacing it with a newer, more efficient model."

"Room Air Conditioners—EER
Room air conditioners generally range from 5,500 Btu per hour to 14,000 Btu per hour. National appliance standards require room air conditioners built after January 1, 1990, to have an EER of 8.0 or greater. Select a room air conditioner with an EER of at least 9.0 if you live in a mild climate. If you live in a hot climate, select one with an EER over 10."
"Energy-Efficient Air Conditioning", US Dept of Energy
http://www.pueblo.gsa.gov/cic_text/hous ... ircond.htm

So, if I read this right, and assuming that the 1w to cool 3w was a fairly efficient current model, then an older A/C might take 2w to cool 3w;
or about 26 watts to cool our 40 watt load.
"Energy Efficiency Ratio (EER) which is the ratio of cooling capacity in Btu/Hr and the input power in watts W at a given operating point."
http://en.wikipedia.org/wiki/Seasonal_e ... ency_ratio

So EER is in units of Btu/Hr/watt
1 Btu/hr = 0.2929 watts (From a unit conversion website)
So to convert EER to watt (load)/watt (powering AC), multiply by 0.2929 watt-hrs/Btu

Thus a window AC unit made after 1990 (EER >=8 ) should remove 2.34 watts per watt of input.
If you live in a warm climate, you should select one (EER >= 10) that can remove > 2.929 watts
(i.e. just about 3 watts removed per watt input), which is the same as the example from Wikipedia above. (It is nice when things cross-check.)


So, for an older AC unit, the 40watt load might consume about 66watts of total power (load + AC) during cooling season. Poorly maintained or less efficient A/C might make it worse, and well maintained, more efficient or more modern A/C might make it better, down to about 53 watts or less.
Also, as the computer will raise indoor temperatures, it will lengthen the cooling season (at least a little).

All told, even assuming it replaces some electric heat in winter, still going to cost about extra $35-45/year to run the thing 24/7,
and still responsible for 600+ extra pounds of CO/2 (etc.) in the air
Far better turn it off when not in use.

[Final paragraph based on:
to estimate cooling/heating season from eyeballing climate data for Waco TX, (arbitrarily chosen point in Texas)
cost electricity 0.11c/kw-h (approx Texas average for 2006)
Greenhouse gas emission from http://www.epa.gov/cleanenergy/energy-r ... lator.html
]

KnightRT
Posts: 100
Joined: Sun Nov 21, 2004 11:13 pm

Post by KnightRT » Wed Feb 13, 2008 9:56 am

You would do better with Firewire or USB. Either will break 30 MB/sec. You'd have to have a seriously optimized gigabit network to manage that, which wouldn't work anyway based on the comments about sharing bandwidth for both the drives and the ethernet card on the same PCI bus.

Shaman
Friend of SPCR
Posts: 278
Joined: Sun Jan 28, 2007 8:34 pm
Location: Portugal

Post by Shaman » Wed Feb 13, 2008 2:02 pm

To all of you running the 'old machine in the closet', do you ventilate the closet with a fan or do you just stuff it in any closet and hope for the best?

MiKeLezZ
Posts: 110
Joined: Sun Feb 20, 2005 8:00 am
Location: ITALY
Contact:

Post by MiKeLezZ » Wed Feb 20, 2008 2:35 am

6 meters are not so much: you could build a USB cable by yourself, by using a ethernet cable (FTP Mediatwist by Belden would be the top), minimum 24AWG (stay away from 26AWG patch cords).
I think 30MB/s should be easily attainable.

Post Reply