Comparing External RAID Housings

Features
By Marcel Binder
published

Backing Up Data To A Hard Drive

In times of increasing memory capacities, backing up your data isn’t quite as easy as it was a few years ago. Optical media is totally unsuited for saving the volumes of data that are generated today. Well, what could be easier than backing up your data by simply copying the contents of an internal drive to an external one?

Hard drives are available at low prices, around 10 cents per gigabyte, and there are two primary ways of connecting an external drive to a computer: USB 2.0 and eSATA. We have already introduced some of the adapters that make connecting an external hard drive to a PC easier in this story on storage accessories.

Connecting via USB 2.0 or eSATA?

Connecting via USB 2.0 works without problems on the vast majority of computers. eSATA drives can also be connected to and disconnected from the computer without needing to restart the operating system, just like a USB memory stick. When using eSATA to connect, you must ensure that the controller is capable of AHCI mode—only then is it possible to connect/disconnect devices without restarting. The only thing missing with eSATA is an icon in the task bar which enables you to safely remove devices.

In order to be able to operate the external drives in an appropriate manner, it also makes sense to acquire a drive housing. It is now possible to purchase units that can support more than one drive. This article investigates what can be expected from a housing designed for multiple drives.

Marcel Binder
Marcel Binder
25 Comments Comment from the forums
  • rockbyter
    did i miss the part about heat and noise?
    Reply
  • Aragorn
    Did anyone else think that the thumbnails of the charts were utterly useless. Why don't we get nicely sized images in THG reports anymore?
    Reply
  • Discussion about external desktop storage and no mention whatsoever of Firewire? *yawn* call me when you have a serious storage article. Firewire is the defacto standard in the pro desktop market, and also of course with all Apple systems. It's faster than USB 2.0 in every benchmark. It's more flexible and mature than eSata. And with Firewire 3.2 Gb/s coming later this year, it's about to get reeeeally fast. I have five external disks (including 2 raid arrays) and all are Firewire 800 connected.
    Reply
  • hawler
    I wish firewire would just die with the upcoming release of USB 3.0 which will be fast 4GB/s and more common. It really is annoying to have both of these on a computer when you could simply have just one of them. Id rather have 10 USB slots then 8 USB and two firewire on my computer. I knwo this isn't goign to happen but there simply is no need to have both, I realize currently it is faster but it won't be soon, and when it was first made they should have tried to make it a new version of USB so that there wouldn't be 2 standards.

    Thats just my opinion on it, im sure people who use a lot of firewire products (i only use it for my ext HDDs but) might disagree but the idea of having just one I/O choice to me is better...its like display port for monitors...why oh why didn't they just leave it with DVI/HDMI
    Reply
  • @ hawler: USB is NOT a replacement for firewire! There's a reason that ALL pro audio equipment uses Firewire instead of USB. There's a reason that ALL camcorders can stream video only over Firewire and not USB.

    It's called "Isochronous transfers". Critical when you're dealing with real-time audio or video. USB doesn't provide that. Also makes bulk data transfer (like backups, for instance) perform more consistently.

    USB was never designed for bulk data transfer. That's why it sucks so badly at it. Ever wondered why a 480 Mbit USB2 connection (That's 60 MB/s) can barely achieve between 35 MB/s in real world transfers? That's because the protocol sucks at bulk data transfer. USB was designed for keyboards and mice. To replace low-speed serial ports. Not for high speed bulk data transfer. The USB protocol is inherently deficient in this regard.

    Firewire, on the other hand, was designed *specifically* for bulk data transfers. It's obvious when you look at its efficiency at these kinds of tasks. Firewire 400 (that's 50 MB/s) achieves around 42 to 45 MB/s in real world performance. Far FAR more efficient than USB at moving data.

    My vote would be for ALL external data storage, audio, and video devices to be firewire only. Make everything else USB.
    Reply
  • njalterio
    For those of you asking about firewire, many companies do not like to use firewire because of security issues. Firewire devices communicate through direct memory access. There is no operating system intervention. This is why many companies will have their IT staff remove firewire expansion cards or disable them.
    Reply
  • @ njalterio: Companies? IT departments? What kind of company IT department directs their employees to backup the PC's individually using external disks??

    Firewire does indeed use DMA. That's another advantage it has over USB, at least in terms of performance. Everyone knows from back in the PATA disk days, that DMA transfers are way faster than non-DMA transfers.

    But for professional audio/video, there is only one option and that's Firewire. No such thing as pro a/v products that use USB. They just don't exist. So when you say that "companies disable fw interfaces" I suppose it depends on what sort of company you're talking about. Not a production studio that's for sure!!
    Reply
  • xxsk8er101xx
    There is this program called Hotswap 4.0.1 i think it is. or maybe 4.1.1. I forget. But it's called Hotswap and it allows you to have that add/remove icon for harddrives. It works for cd-roms, ide drives, fixed drives ... it's an amazing program and best of all - it's free!

    Again it's hotswap! 4.'something ... http://www.softpedia.com/get/System/OS-Enhancements/HotSwap.shtml it's an amazing tool and it works very well. Solves the problem listed on page 1 about no add/remove icon.
    Reply
  • GreenPower
    All my applications are installed on the C drive, which is a 500GB $79 WD unit. I buy a second identical drive and hook it up to an extra 18" sata cable and power right at the edge of the pc case chassis.
    I use Acronis True Image disk utility to make and exact copy when the system half way reboots. Then I turn off the power and swap disks. A few applications like Photoshop can still detect they have been copied. But besides this its a 5 minute replacement if my HD ever gets corrupted.

    Otherwise it takes about 4 LONG days to rebuild the system from scratch.
    Five minutes vs four days. Go figure!
    Reply
  • GreenPower
    Always run the long format and surface scan any new disk to check for bad sectors. Then re-scan it after its been copied and re-booted with. Only then can you state that you backup is worthy.
    Reply