network storage / external storage questions?

3 replies [Last post]
Stuna2150's picture
Joined: 08/14/2010
Posts: 50

Ok so i have a 1.5TB external hard drive thats almost full 86GB left :( anyways i want to upgrade but instead of getting a 3TB drive i was thinking about getting a triple drive bay external device that supports raid (preferably raid 5) for future proofing my constant growing data consumption.

with that ^ said I was thinking that instead of just having a data bank like above where you have to be linked via cable to it to access data i wanted to be able to share the data with all my devices (laptop, tablet, desk tops) through my wifi.

anyways my questions for all this is as follows.

what are some good 2-3 bay external enclosures are there that wont break the bank and support raid 5 or 1.

would a network drive running off of a router eliminate the bottle neck of a usb cord? Would i see MUCH faster speeds through wifi and would downloading large files from my storage slow down a download im currently doing on a device?

would doing some of this cause security risks? or cause some devices from being able to access data?

any answers would be great!

This person is in a serious relationship with technology <3

limeDk's picture
Joined: 04/22/2011
Posts: 124

well you could get a NAS server

Manic Mouse
Manic Mouse's picture
Joined: 02/01/2007
Posts: 118

There are two ways you can go depending on how you want to be able to access your data:

1. A Direct Attached Storage (DAS) box that attaches via USB (2 or 3) or eSata
2. A Network Attached Storage (NAS) box that attaches via your home network.

In order to handle Raid 5, you need at least 3 drives. I don't think I have ever seen a 3-bay NAS or DAS box. The most popular that I have seen have 1,2,4,5,8 or 10 bays (price goes up depending on bay count). 2-bay boxes are relatively cheap but only have raid support for raid 0 (striped) or 1 (mirrored). Moving up to 4 bay or higher will give add raid 5 (striped with 1 disk parity/fail tolerance) and raid 10 (striped + mirror) or in some cases a vendor-custom raid technology. 5 bays + will allow raid 6 (striping + 2 drive parity/fail tolerance). Remember that using raid 5 or 6 requires some intelligence in the box to handle generating parity for all data written to the drive. The more powerful the NAS/DAS processor, the faster it will be in handling Raid 5 or 6.

Data Acessibility

NAS attaches via Ethernet or Wireless via your home router and can be accessed by any computer or device (i.e. cell phones, tablets and media streaming boxes) you have attached to that network. NAS boxes usually contain low power Linux-based computers and up to 2GB of memory to act as a true network server. Any computer in your network can access these shared drives as a network drive. Some NAS boxes even let you set up a personal 'cloud' service.

DAS connects to a single computer and is not shared unless you set that computer to share out the drives provided by that DAS box. A DAS does not have the intelligence of a NAS box. It does have a processor fopr calculating parities and multiplexing your drives internally, but that is about it. DAS boxes are somewhat cheaper than NAS boxes because of this.


DAS boxes, because they can be connected using eSATA or USB 3.0 have higher performance than a NAS. You pay for that performance in the lack of accessibility of your data. There are some very nice DAS boxes out there, but being a less popular solution there is somewhat less selection than for a NAS box.

NAS boxes are limited to the speed of a gigabit Ethernet cable. While this may sound slow, an GBe connection can provide about 100-120MB/sec throughput. The actual throughput you get depends directly on how powerful your NAS box is. A single core 1Ghz Marvell-based unit with half a gig of memory and raid 5 may not hit anywhere near that number (usually somewhere in the 60-50MB/sec range). A dual core 2.13 Atom box with 2 GB memory can actually saturate that bandwidth pretty easily without getting hot. Of course you will pay a premium for this latter class of NAS as these are usually targeted to small business rather than personal use. Expect to see pricing for the former as a 4-bay NAS in the $400 CA/US range. The latter will set you back anywhere between $650 to $800 CA/US.

My own experience

I have been using NAS (and home-built storage servers before that) for several years now and have evaluated everything from the cheaper Marvell-based NAS, to the above mentioned dual core Atom-based monster that I use now. I have also tried out a few of the DAS options (to varying degrees of success). I use my NAS to store all of my data and even have backups of it that take place automatically a couple times per week. My NAS currently has 4x3TB Western Digital 'Green' 5400RPM drives arranged in Synology's variant of Raid 5. That gives me a total of 9TB total space. Connecting to that NAS I have 4 household computers and 3 network streaming devices (Boxee and WD TV Live). Also there are 3 smartphones and a Galaxy Nexus 7 tablet connecting to it.

Performance wise, I find moving files between my computer and the NAS (either Write or Read) is every bit as fast as, and sometimes faster than, than moving those same files across internal hard drives. In short for performance I do not see any downside at all to storing my data on my home network. I DO used a wired Ethernet connection though. You will not get that kind of throughput even with 450Mb/sec Wireless N though the new 1300Mbit/sec 802.11ac standard may actually beat it.

Hope that helps.

Mark Baker

Asus P9X79 Deluxe, Intel i7 3930K @4.5Ghz, 64gb G.Skill RipjawsZ 10-10-10-30 PC3-12800, Sapphire HD 7950 3GB, OCZ Vertex 4, Vertex 3 & Intel 510 SSDs, wrapped in a CoolerMaster HAF XM case

eire1274's picture
Joined: 09/12/2003
Posts: 1110

Manic Mouse, the only thing I disagree with is NAS storage limited to gigabit. Off the shelf in the cheap bracket, yes, you are right. However, there are lots of off the shelf enterprise machines that have 10gb/s and even fiber connections... but you'll pay for them.

You can also use older PC hardware with products like FreeNAS (FreeBSD based), Openfiler (Linux based), and other pre-built free NAS OS systems that can run very efficient RAID arrays. ZFS (formerly of SunOS) is also getting a lot of notice as a RAID alternative, with the benefit that disk sizes don't have to be the same, yet it also replicates data so single (ZFS1), double (ZFS2), or more disk failures, based on array configuration, do not affect operation AT ALL and all data will survive.

I'm a big supporter of FreeNAS (hence first on the list) and ZFS has been, with a little coding in the scripts, very stable on a 700Mhz Athlon with a dinky 768Mb of memory. My array is now approaching full (around 4Tb usable on SATA and USB drives) and saturates a gigabit link DESPITE the USB drives having a slowdown effect due to their connection. I'm intending to move up to a 10gb/s card and more SATA drives, but this of course will mean a complete rebuild of the server as the motherboard of course only has 33Mhz PCI slots which just barely supports gigabit. However, for a few hundred dollars you can build a small system with hot-swap bays, and adding a 10gb/s card (supported by the base OS) would only be another $300-400 as a future upgrade, if needed.

Nick McDermott