Network Attached Storage device

[MarkF]

After some advice and hopefully avoid any pit falls.

I run a LAN at home with 4 computers attached three of which have users the fourth is my Rfactor server. I used to run a windows 2003 server with roaming which was great but too many issues for me to keep ion top of. I am currently using a NAS HDD but it is only 10mb LAN and very slow transferring data.

I am looking for a NAS device with 1000mb transfer and either RAID for mirror or ability to back up to a USB drive. Mainly it will be used for storing documents, movies, mp3's and a downloaded stuff from the net and all the family photographs.

The important thing is a back up either RAID or USB external drive. Size is around 500GB but obviously I don't want to spend too much. Currently looking at a Buffalo Linkstation 500GB.

Anyone been down this path already?

[Rouke]

this will prolly sound dumb cus i dont realy know what i'm talking about but that never stopped me before so...

isnt raid 2 HDD's so they can speed up but also have the same data on each HDD?
and isnt either of them not the backup HDD incase things go wrong?


anyways, , currently i have 4 extrernal HDD's, the smaller ones from years back obviously, the bigger ones from recent purchases.
they get cheaper and cheaper every month. 500GB will most likely not set you back too much, i think its ideal for backups.

[MarkF]

You are quite right Rouke, but you can set RAID to either mirror or speed it up by copying bits of data to both drives which in effect copies a single instance of the data so no back up. Mirror will copy the same data to both drives giving a back up mirror image of the other drive, so one drive fails you have an instant back up. Speed wise the HDD is always going to be quicker than the LAN connection so Mirrored back up is my option in RAID.

I also want to avoid a USB because that means the computer with the drive attached needs to be on or move the drive, i just want it simple so whenever a computer is on it has access to that drive.

Speed is important too, a couple of computers accessing the drive over a LAN throttles the LAN connection so a Gigabyte connection is essential, also I want to put our email accounts there together with My Documents and browser settings. In effect if I have a HDD failure on my computer I reinstall windows and still have access to my data which other than through back up would have been lost. Now USB external drives are great for a single computer solution. Unfortunately i progressed beyond that many years ago and the Internet and computer is as much used by all the family here as the TV is for entertainment and storage.

The NAS I am looking at does a whole lot more too, with multimedia station, web hosting, instant back up of usb devices, mail server if I wish and so on.

[Ray Walton]

On the subject of RAID there are Rouke for general use on home machines two popular RIAD modes.

Mode 0 or Striping which is not really true RAID. This splits the data between two disk writing 4 bits of each byte to one disk and at the same time the other 4 bits to the second disk in the array. This as you would gather speeds up disc writing and reading tremendously though in practice not fully by a factor of two as it may in theory seem to do. Note that if one disk fails then without a good back up your data will be lost so there is NO Redundancy as the RAID name would imply and thus why I say not considered a true RAID mode.

Mode 1 Mirror is as the name implies where one disk has its data exactly mirrored bit for bit on the other disk in the array. This in fact does slow down writing but has no significant impact on reading speed as only one disk needs reading anyway. But it does mean that if one disk fails the other can take over seemlessly so offers some level of back up. Problem is if you get a virus it will damage both disks in the array equally and thus is not a reliable back up like the use of a separate USB or NAS hard drive with a snapshot image back up that can be used to restore to a previous and pre virus damage time.

So to summarise:-

RAID Mode 0

Main Advantages :-
Fast disk writes and reads.
Full capacity of the two disks utilised so no wastage of disk space.

Main Disadvantages:-
No parallel redundancy, if one disk fails you lose all your data without professional recovery, so in effect doubles the chance of a disk failure and data loss though disk failures are relatively rare these days. So absolutely no built in level of back up.

RAID Mode 1

Main Advantages:-
Good protection against disk failure losses so offers some level of back up as each disk in the array is a mirror of the other one at all times.

Main Disadvantages:-
As identical data has to be written to both disks in the array it is significantly slower writing data to the disks.
You only get half of the total capacity of the two identical drives so very wasteful of disk space.
Does not provide a back up from virus infections and related data corruption.

[Antonio Wojahn]

Hi,

of course, there is the option to have RAID 0+1 and have it both ways, though I consider that too expensive to maintain. Plus, Mark has already pointed out it's the ethernet which is the bottleneck here. I think 10GB ethernet is available, though again, too expensive. You seem to be up to the task already, Mark!

Ciao,
Antonio