Mac RAID solution

[dcw@pr]

does anyone know of a hardware RAID solution for Mac, that isn't super expensive (i.e. like the XServe). At the moment I am using two external 1Tb LaCie drives, with an automated software backup. Th problem with this is that the drives are self contained RAID 0 setups with 4 250gb drives, and if one of them goes, I lose everything on that rive, and it takes ages to get a replacement. What I would ideally like is a RAID enclosure with space for at least 1Tb, that I can hot swap drives into if necessary. Does such a thing exist? And on a related note, I have never quite got the hang of how RAID 5 works - how many 500Gb drives do you need to have 1Tb of fault tolerant data?

[puggit]

Raid 5 works as x+1.

So if you have 3 disks which is Raid 5(2+1), then x=2. Therefore you have 2x500GB and one disk as parity.

If you are using Raid 5(4+1) then you have 4x500GB plus one disk for parity...

Can't help except to point towards Xserve/Xraid as I work with Apple on selling this - but I can give pointers to software other than Retrospect or NetVault...

[dcw@pr]

Is it sensible to run software RAID on anything other than 0 or 1? I woul dhave thought the CPU overheads would be quite high, plus of course the reliability....

[_dobbo_]

What about one of these:

terastation

Allows for either 1TB of space, or 750GB with fault tolerance.

Hot swapable also I believe.

[dcw@pr]

_dobbo_ said:

What about one of these: terastation Allows for either 1TB of space, or 750GB with fault tolerance. Hot swapable also I believe.

brilliant, that is just what I am looking for. I know that 500GB HDs have just come out, so maybe soon this will be available with 1.5TB fault tolerant. thanks Ben

[magic torch]

_dobbo_ said:

What about one of these: terastation Allows for either 1TB of space, or 750GB with fault tolerance. Hot swapable also I believe.

From a qualified Mac Technician.

[dcw@pr]

they have a 2TB version coming out at the end of the month!

I was just speaking to one of their guys on the phone, he couldn't tell me what sort of transfer rates I would be getting. At the moment I can get 60mb/sec real speed across an FW800 connection, can anyone say the sort of thing I would be looking at with this over gigabit ethernet?

[_dobbo_]

I'm qualified to say I don't see the point of paying more for mac specific stuff when you can get something to do the job for a fraction of the cost. Since it's network attached it doesn't matter if it's PC Mac or Unix, it's all good!

I guess it doesn't have a smoked glass cover and an apple badge, the fools, if they added those and wrote "mac only" on the box they could charge 5 times as much...

[_dobbo_]

dcw@pr said:

can anyone say the sort of thing I would be looking at with this over gigabit ethernet?

Gigabit transfer rates are a theoretical maximum of something like 128MB per second, however in practice you wont see this, but should get 2/3rds of it, so no slower than your current speed.

I suspect the limit though will be the disk write speed, if those terastations use software raid (which I fear they do) then writing the data and the parity will slow this down. Still, for the money I can live with that, which is why we have one!

[dcw@pr]

don't suppose you could do a quick read test on your one could you? would be very interested to know how fast it is

[ThatPhilBrettGuy]

Slow :- www.tomsnetworking.com/2005/05/25/review_terasta/
Fast :- www.tomsnetworking.com/2006/03/03/infrant_readynas_nv/

And yes the TeraStation does do it's RAID with LINUX software RAID.

[HiRich]

I may be talking out of my hat, but I believe the G5 towers come with dual gigabit ethernet, precisely for RAID work.
One port is dedicated to network communication, leaving the second 'free' (of network traffic) for your RAID ethernet box. Worth researching.

[_dobbo_]

Ours isn't wired to gigabit so a read test wont tell you anything useful I'm afraid.

[dcw@pr]

HiRich said:

I may be talking out of my hat, but I believe the G5 towers come with dual gigabit ethernet, precisely for RAID work. One port is dedicated to network communication, leaving the second 'free' (of network traffic) for your RAID ethernet box. Worth researching.

my G5 has only one ethernet port, but it was one of the first models around, so maybe the later ones are different

thanks phil, that is good to know, i would have been pissed off if i had bought a drive with a 15mb/sec transfer rate. Looking like i may well get the 2tb Infrant one now. Its a bit more pricy but looks to be worth it, and if I buy the case and drives seperately I can get a spare drive for the same price as buying everything together.


>> Edited by dcw@pr on Tuesday 9th May 13:30

[ThatPhilBrettGuy]

dcw@pr said:

HiRich said: I may be talking out of my hat, but I believe the G5 towers come with dual gigabit ethernet, precisely for RAID work. One port is dedicated to network communication, leaving the second 'free' (of network traffic) for your RAID ethernet box. Worth researching. my G5 has only one ethernet port, but it was one of the first models around, so maybe the later ones are different thanks phil, that is good to know, i would have been pissed off if i had bought a drive with a 15mb/sec transfer rate. Looking like i may well get the 2tb Infrant one now. Its a bit more pricy but looks to be worth it, and if I buy the case and drives seperately I can get a spare drive for the same price as buying everything together. >> Edited by dcw@pr on Tuesday 9th May 13:30

I know someone with a TeraStation and another with the Infrant box.A part from the price the Infrant box can't be beaten. Until the latest firmware the TeraStation crashed every 2 days or so and under load. I'm going to get a Infrant box. Not many UK suppliers though.

[dcw@pr]

ThatPhilBrettGuy said:

I know someone with a TeraStation and another with the Infrant box.A part from the price the Infrant box can't be beaten. Until the latest firmware the TeraStation crashed every 2 days or so and under load. I'm going to get a Infrant box. Not many UK suppliers though.

only one supplier as far as I can tell. My only problem with it is apparently it is quite noisy, I will have to look at having it in another room or something.

[magic torch]

_dobbo_ said:

I'm qualified to say I don't see the point of paying more for mac specific stuff when you can get something to do the job for a fraction of the cost. Since it's network attached it doesn't matter if it's PC Mac or Unix, it's all good! I guess it doesn't have a smoked glass cover and an apple badge, the fools, if they added those and wrote "mac only" on the box they could charge 5 times as much...

Never pay extra for Mac specific hardware.

[dcw@pr]

have just ordered an Infrant ReadyNAS NV and am about to order 5 500GB HDs. Thanks for the help.

[dcw@pr]

stop press!!! have just cancelled my order for the Infrant, will be getting one of these,

www.lacie.com/uk/products/product.htm?pid=10600

£1200 from Dabs

[ThatPhilBrettGuy]

dcw@pr said:

stop press!!! have just cancelled my order for the Infrant, will be getting one of these, www.lacie.com/uk/products/product.htm?pid=10600 £1200 from Dabs

Only issue is there's no network interface. Diffrent type of product really. Great if you've only got one machine you need storage for though.