External Raid/eSata

[thefredelement]

Just curious as to what external raid enclosures and eSata cards people are using. There seems to be a lot results and a lot of poorly reviewed stuff out there. I was thinking Lacie but don't like that I can't run to a store to replace a failed drive.

I'd like 4 drives, 2TB each in a raid 0+1, a hot spare would be nice but isn't killer. It seems eSata would be best as an interface through an add on PCI card.

What do you use or would you recommend?

 

[nanofrog]

What exactly are you trying to do?

For example, is it primary storage or backup? If it's primary storage, what kind of performance are you after?

There's a lot involved with figuring out what you actually need, so I'd recommend searching here in MR to start with (lots of threads on RAID). Lots of reading, but you'll be better off IMHO, as you'll be able to make an informed decision based on actual need.

 

[slughead]

I'm using a RocketRaid 2134 card I bought many years ago. It's still working great.

My enclosure I built on the cheap from retail PC parts:

https://forums.macrumors.com/threads/1303010/

 

[thefredelement]

Oh I have been, a lot of the threads seem to be a bit dated, but I guess there haven't been too many recent breakthroughs in raid technology.

The goal is to have 4TB of usable space as my secondary storage. I boot and have apps on a 256GB SSD and have been keeping my current audio projects there. I have some older media and projects that I'd just like to keep in a usable way and know that it's backed up.

The performance for this doesn't need to be earth shattering, I don't need an enterprise grade, server class external raid. I just don't want something that's going to throw the array if one drive fails. Right now I have a 2TB Hitachi with all of this type of data on it and the read/write is OK, I'd like better, but primary goal is 4TB of set it and forget type of backed up storage.

What exactly are you trying to do?

For example, is it primary storage or backup? If it's primary storage, what kind of performance are you after?

There's a lot involved with figuring out what you actually need, so I'd recommend searching here in MR to start with (lots of threads on RAID). Lots of reading, but you'll be better off IMHO, as you'll be able to make an informed decision based on actual need.

 

[slughead]

For 4TB, I'd recommend FOUR 2-TB drives in a RAID 10. Software RAID via OS X will ensure you can plug the array into different machines and eSATA cards / eSATA ->USB adapters without issues.

Some people like RAID-5, but inexpensive RAID-5 cards have fatal flaws that just aren't worth the extra space you get (your card needs an on-board battery, essentially, otherwise you're risking your data). Since you're only wanting 4TB, why not just buy an inexpensive eSATA card and use your Mac's software RAID to put it in a RAID 1 or 10?

Here's my RAID 10 that Disk Utility setup for me (it uses 1TB drives, you're wanting 2TB):

Go to http://newegg.com to look at prices. Currently 2TB drives are about $60/TB, so with redundancy that's $120/TB. 3TB drives are the same price/TB, but 4TB drives are about 25% more $ / TB.

I just priced them out today

 

[thefredelement]

Slughead, thanks for that, I looked in to OS X raid but kind of got the impression a built in controller on an external enclosure was better for portability and moving RAID controls off the computer, that could be the wrong impression.

the last time I dealt with RAID was setting up RAID5s in HP servers in the late 90s/early 2000s, so it def. has been awhile...

I think RAID 0+1 is my best bet as far as performance and backup go.

For 4TB, I'd recommend FOUR 2-TB drives in a RAID 10. Software RAID via OS X will ensure you can plug the array into different machines and eSATA cards / eSATA ->USB adapters without issues.

Some people like RAID-5, but inexpensive RAID-5 cards have fatal flaws that just aren't worth the extra space you get (your card needs an on-board battery, essentially, otherwise you're risking your data). Since you're only wanting 4TB, why not just buy an inexpensive eSATA card and use your Mac's software RAID to put it in a RAID 1 or 10?

Here's my RAID 10 that Disk Utility setup for me (it uses 1TB drives, you're wanting 2TB):

Image

Go to http://newegg.com to look at prices. Currently 2TB drives are about $60/TB, so with redundancy that's $120/TB. 3TB drives are the same price/TB, but 4TB drives are about 25% more $ / TB.

I just priced them out today

 

[-hh]

What I did last summer as part of a storage expansion was to pick up a pair of Newer Technology's Guardian Maximus external RAIDs.

Granted, these are only two (2) HDDs, and only do RAID-1, but the RAID is done in the enclosure's hardware on its own, so they're easy to move between Macs. It has a quad interface (USB2/3+FW800+FW400+eSATA) and it ships with a complete set of cables, so the overall product is quite conveniently turnkey, which makes it a breeze to get it all set up & running.

Presently, they're selling their 2 x 4TB HDD (3.5") system for $888, as well as a bunch of lower capacities, all the way down to a bare "Add your own drives" kit for $140. The enclosure is designed to be easily opened/closed to install/replace drives...IIRC, it just needs a standard #0 phillips screwdriver.

For my applications, my external storage doesn't need to be RAID-0 speedy; I'd buy them again.

-hh

 

[nanofrog]

The goal is to have 4TB of usable space as my secondary storage. I boot and have apps on a 256GB SSD and have been keeping my current audio projects there. I have some older media and projects that I'd just like to keep in a usable way and know that it's backed up.

The performance for this doesn't need to be earth shattering, I don't need an enterprise grade, server class external raid. I just don't want something that's going to throw the array if one drive fails. Right now I have a 2TB Hitachi with all of this type of data on it and the read/write is OK, I'd like better, but primary goal is 4TB of set it and forget type of backed up storage.

For a backup system, you don't need to go crazy then, as you can sacrifice blazing speed for a much more affordable solution.

Given what you seem to be interested in doing, consider the following equipment:

• OWC's Mercury Elite Pro Qx2 (RoC based, which is a simple controller chip)
• Buy the drives of your choice
• PCIe eSATA card

It would do what you need, and at an affordable price as well.

Slughead, thanks for that, I looked in to OS X raid but kind of got the impression a built in controller on an external enclosure was better for portability and moving RAID controls off the computer, that could be the wrong impression.

An RoC based enclosure would be a better solution for portability, as it's internal to the enclosure. If it's done via the OS, things can get messy really quick when transferring from one system to another.

I think RAID 0+1 is my best bet as far as performance and backup go.

10 (stripped mirror) is safer than 01 (mirrored stripe), and happens to be what the linked enclosure will do (the order the configuration is setup as does matter in this case).

You can find the details on Wiki (IIRC, look under the specifics of level 10 on the RAID Levels page).

 

[thefredelement]

Have you used that one? It seems to have some really negative reviews out there.

For a backup system, you don't need to go crazy then, as you can sacrifice blazing speed for a much more affordable solution.

Given what you seem to be interested in doing, consider the following equipment:

• OWC's Mercury Elite Pro Qx2 (RoC based, which is a simple controller chip)
• Buy the drives of your choice
• PCIe eSATA card

It would do what you need, and at an affordable price as well.


An RoC based enclosure would be a better solution for portability, as it's internal to the enclosure. If it's done via the OS, things can get messy really quick when transferring from one system to another.


10 (stripped mirror) is safer than 01 (mirrored stripe), and happens to be what the linked enclosure will do (the order the configuration is setup as does matter in this case).

You can find the details on Wiki (IIRC, look under the specifics of level 10 on the RAID Levels page).

 

[philipma1957]

a very good quality 2 drive unit


TowerSTOR TS2CT - 2 Bay SATA to USB 2.0 / eSATA / 1394a / 1394b RAID Enclosure













ve unit is this.

 

[nanofrog]

Have you used that one? It seems to have some really negative reviews out there.

No. All of my stuff is on Areca controllers (I need the performance, capabilities, and additional features such cards offer). It's expensive though, so if it's not an absolute necessity, better to save the funds IMHO.

Other members here on MR have however, and have had good results out of them. The biggest complaint I recall is speed, but RoC's are not fast. Not by a long shot. But the speed will be fine for a level 10 used as a backup storage pool (RoC based enclosures in general).

As always though, YMMV for a number of reasons (bad unit, bad batch, switched chip suppliers, ... sorts of things).

 

[thefredelement]

You guys all are great, thank you very much for helping me out here.

I'm considering this thing:

http://www.amazon.com/Sans-Digital-TowerRAID-Hardware-TR5UTP/dp/B003YDZDZW/ref=cm_cr_pr_product_top

I've done some searching on the forum here and came across a member who liked his, but that was a few years ago. Out of the limited reviews, it seems to be better than the limited reviews from the OWC unit.

I like that it already comes with the eSata card.

I wonder if I should just bide my time with what I'm currently using (internal 2TB Hitachi, Timemachined to a 2GB internal WD Green), save up and go with a more robust external enclosure with a real internal RAID card.

Though I guess I could just Timemachine the RAID volume and if the array gets destroyed for any reason, rebuild it and bring it back via the Timemachine.

It's taking me a while to get my at home situation back up to snuff, including a recent used MP purchase which has been great. I had a storage drive fail on me back in '09 and actually still haven't gotten over the hit of losing all that data, about 10 years worth of music (over 200 personal projects), photos, home videos, web dev projects (countless) just all gone. So I want to do this right, though there's something to be said for enterprise taste, with an @home budget...

No. All of my stuff is on Areca controllers (I need the performance, capabilities, and additional features such cards offer). It's expensive though, so if it's not an absolute necessity, better to save the funds IMHO.

Other members here on MR have however, and have had good results out of them. The biggest complaint I recall is speed, but RoC's are not fast. Not by a long shot. But the speed will be fine for a level 10 used as a backup storage pool (RoC based enclosures in general).

As always though, YMMV for a number of reasons (bad unit, bad batch, switched chip suppliers, ... sorts of things).

 

[ogs]

i prefer raid 5 myself. but then again i use external raid setup as archival space, where my data can never be lost.

0+1 is alright though. two sets of two drives via raid 0 for performance, then the two sets of two drives in raid 1 for striping.

my deal with that is, if a single drive fails in either pair, the pair is lost still....
http://en.wikipedia.org/wiki/File:RAID_0+1.png

again, it depends on how you're going to use your raid array.
also, software raid is scary.


edit: sorry just read upwards... "enterprise taste @ home budget" .... drobo?

 

[nanofrog]

You guys all are great, thank you very much for helping me out here.

I'm considering this thing:

http://www.amazon.com/Sans-Digital-TowerRAID-Hardware-TR5UTP/dp/B003YDZDZW/ref=cm_cr_pr_product_top

Sans Digital makes decent gear.

I only recommended the OWC product due to it's cost (even after added the eSATA card, it's half what the Sans Digital is selling for on Amazon).

They're really not that different at all (same concept, but perhaps a different RoC chip). Aesthetics of course, but they're not that different in that regard either.

Up to you.

Though I guess I could just Timemachine the RAID volume and if the array gets destroyed for any reason, rebuild it and bring it back via the Timemachine.

This statement makes me think the 10 solution is for primary data, not backup.

If this is the case, an RoC based product can work, but be warned it's neither as fast or as robust in the event of a failure (i.e. not as easily recovered in case of a fault).

Proper RAID cards would definitely have the advantage here, but it's quite expensive (card, disks, and enclosures if it's to be external or requires more drives than can be fitted internally in a MP).

...there's something to be said for enterprise taste, with an @home budget...

Yep. It's called impossible.

Seriously though, there's quite a bit to it.

 

[thefredelement]

It is for primary data, now that I think about it, I got a little backwards in my head with having my current SSD backed up to a dedicated time machine disk, I keep my current projects on the SSD and then bring them back to my 2TB when I'm done, so in an ideal world the array would take the place of the 2TB drive, plus a small partition that I can keep sync'd with the SSD, then something working as a Timemachine for the array + SSD.

I'm scoping out cards now, boy it's been awhile since I've dropped an Adaptec SCSI in to an HP server!

Sans Digital makes decent gear.

I only recommended the OWC product due to it's cost (even after added the eSATA card, it's half what the Sans Digital is selling for on Amazon).

They're really not that different at all (same concept, but perhaps a different RoC chip). Aesthetics of course, but they're not that different in that regard either.

Up to you.


This statement makes me think the 10 solution is for primary data, not backup.

If this is the case, an RoC based product can work, but be warned it's neither as fast or as robust in the event of a failure (i.e. not as easily recovered in case of a fault).

Proper RAID cards would definitely have the advantage here, but it's quite expensive (card, disks, and enclosures if it's to be external or requires more drives than can be fitted internally in a MP).


Yep. It's called impossible.

Seriously though, there's quite a bit to it.