Internal Raid vs. External Raid?

legocitytruck

Senior member
Jan 13, 2009
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Which is more reliable, having multiple internal hard drives connected to hardware based RAID (such as a south bridge) or an external enclosure that supports multiple drives and has integrated RAID support?

Will the reliability differences between the two setups be eclipsed by the varying levels of reliably that result from manufacturing variability?
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
I don't consider the south bridge option to be a "hardware based" controller.
Yes, technically the south bridge is "hardware", but I still don't consider it a "hardware based" system.
That's my opinion, others may differ... What a wonderful world we live in. :laugh:

Internal and external reliability depends on several factors, like HDs, controller and power supply quality.
 

pjkenned

Senior member
Jan 14, 2008
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www.servethehome.com
You forget a third option which is internal controller, external storage :) For example you could get an Adaptec 3085 (and I have one) and use an external enclosure or use a conversion cable to go internal. You can also go from internal -> external for about $25 per 4 lane connector (or much cheaper if you get a SATA rather than SAS/SATA controller).

Personally, that really depends on what you are doing. Raid 0, I would want internal period. Raid 1 I would be fairly indifferent. Raid 5/6/10 I would want a real hardware card + battery back up on card and for the PC, and no cheapo external enclosure devices.

That being said, if you meant something like a QNAP external device then external raid is fine. But a QNAP device is really a full server system and not an enclosure with a "raid" chip. Also, you only get ethernet connectivity whereas an external enclosure connected to an internal raid card gives you PCIe bandwidth.

Things to consider, but let us know what you are thinking of doing and we can flush it out more.
 

legocitytruck

Senior member
Jan 13, 2009
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Wow a lot of options here. I will have to research these options you mentioned. My current goal is to reliable connect two drives in a RAID 1 format, with the future option of switching to RAID 5 or 6 along with more drives.

You mentioned that you want know cheapo external enclosure connected to an internal card. What qualifies as cheapo?

Also what sort of connection method allows PCIe bandwidth?
 

Blain

Lifer
Oct 9, 1999
23,643
3
81
Originally posted by: legocitytruck
Should Southbridge based RAID controllers not be compared with RAID PCIe cards?
Sure you can compare a southbridge controller with a real RAID card...
They each have similarities and differences. The suitability all depends on end user needs.

Just like a Chevy Cobalt and a Mercedes C300.

 

postmortemIA

Diamond Member
Jul 11, 2006
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southbridge raid is directly connected to chip and has "awesome" performance for low cost. you'd need PCI express RAID card of many bucks to get more performance.

this solution is good for desktop computers, you won't gain much for buying separate hardware card
 

legocitytruck

Senior member
Jan 13, 2009
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Originally posted by: postmortemIA
southbridge raid is directly connected to chip and has "awesome" performance for low cost. you'd need PCI express RAID card of many bucks to get more performance.

this solution is good for desktop computers, you won't gain much for buying separate hardware card

Thanks postmortemIA, how would you compare Southbridge based RAID to a low cost external hard drive enclosure with RAID capabilities?
 

homercles337

Diamond Member
Dec 29, 2004
6,340
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Originally posted by: Blain
I don't consider the south bridge option to be a "hardware based" controller.
Yes, technically the south bridge is "hardware", but I still don't consider it a "hardware based" system.
That's my opinion, others may differ... What a wonderful world we live in. :laugh:

Internal and external reliability depends on several factors, like HDs, controller and power supply quality.

Damn you Blain! *Shakes Fist* BLAAAIIIIN!
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
there are three way of doing raid... pure software, pure hardware, and hybrid.

Pure software aka OS,level raid (ex: ZFS on osol, windows based raid, linux based): slow (comparatively), reliable, free, no single point of failure, easily migrateable, etc
I use pure software raid.

Pure hardware (ex: 300+$ controllers): blazing fast, single point of failure (can be repaired by exact replacement of potentially hard to find hardware in the future), proprietary, non migrateable, etc

Hybrid (motherboards) - all the disadvantages of pure software, all the disadvantages of pure hardware, none of the benefits of either, and a many new disadvantages unique to hybrid (such as array loss on cmos clear) and it being even slower than the pure software implementation.

Hybrid (mobo raid) has one and only one unique advantage... Windows cannot be booted off of a RAID software array (some other oses can!), only a pure hardware or hybrid raid can be used as a windows boot drive. And the pure hardware is expensive while the hybrid is usually "free" (included in mobo price and has a ton of disadvantages and risks)

Anyone that knows anything would tell you to never, ever, ever! use mobo based raid. Actually I went against such advice from several professionals (what with me being a professional myself, and mostly thinking "it can't be THAT bad")... well i was wrong, it was worse than I ever imagined, i didn't give up easily either... i tried various configurations such as raid5 and raid1 on a variety of mobos over of the years, nforce 2, 4, 5, and intel chips (ICH#R)... all were bitter disappointments despite having been given plenty of time
 

sxr7171

Diamond Member
Jun 21, 2002
5,079
40
91
Makes me feel glad I never dabbled into motherboard based RAID. I think I will get to try some hardware RAID soon. Any good cards for just RAID-1 support? I was looking at some of the Areca stuff, but maybe there is something less pricey that gets the job done.
 

postmortemIA

Diamond Member
Jul 11, 2006
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Originally posted by: taltamir


Anyone that knows anything would tell you to never, ever, ever! use mobo based raid. Actually I went against such advice from several professionals (what with me being a professional myself, and mostly thinking "it can't be THAT bad")... well i was wrong, it was worse than I ever imagined, i didn't give up easily either... i tried various configurations such as raid5 and raid1 on a variety of mobos over of the years, nforce 2, 4, 5, and intel chips (ICH#R)... all were bitter disappointments despite having been given plenty of time

... I've been using nVIDIA and intel hybrid solutions for 5+ yrs now, no problem, all I got was performance increase.

is hardware RAID better/ sure it is, but it is expensive.

you are trying to scare people. intel would not make ICH*R solutions that are unstable and unreliable.

simple sequential benchmarks show me that my sequential speed has gone up for over 50%, and that is heck of the deal for $10.
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
that really depends on the SPECIFIC external enclosure in question.

The three categories were referring to raid types you can run internally on a computer. An external storage like this one is basically a computer/chipset that runs some sort of raid and makes the data available via USB, eSATA, firewire, or ethernet to your computer. So the question is, what sort of raid the specific enclosure in question employs internally. I know some use a chip, others have an entire computer crammed inside and run an OS level raid. You basically have to judge each specialized external device like that in its own light, in depth reviews of a specific product really help here (read: anandtech like reviews, not the stuff on newegg)

I would bet that one is probably a controller inside, not a whole PC, and thus like pure-hardware add-in card in drawbacks and benefits; only cheaper to buy and slower. A cheaper card for the PC is usually hybrid, like the mobo based raid, because it knows that it is attached to a CPU that can do the lifting. (and has the same issues of a mobo hybrid raid). But a cheaper external enclosure can't assume CPU and RAM access, so it is often a chip, and those vary greatly in quality and performance. (just like how the jmicron SSD controller is a world apart than the intel SSD controller).
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
Originally posted by: postmortemIA
Originally posted by: taltamir


Anyone that knows anything would tell you to never, ever, ever! use mobo based raid. Actually I went against such advice from several professionals (what with me being a professional myself, and mostly thinking "it can't be THAT bad")... well i was wrong, it was worse than I ever imagined, i didn't give up easily either... i tried various configurations such as raid5 and raid1 on a variety of mobos over of the years, nforce 2, 4, 5, and intel chips (ICH#R)... all were bitter disappointments despite having been given plenty of time

... I've been using nVIDIA and intel hybrid solutions for 5+ yrs now, no problem, all I got was performance increase.

is hardware RAID better/ sure it is, but it is expensive.

you are trying to scare people. intel would not make ICH*R solutions that are unstable and unreliable.

simple sequential benchmarks show me that my sequential speed has gone up for over 50%, and that is heck of the deal for $10.

go reset your cmos and let me know what happens. I am not trying to scare people, just giving them the facts. running mobo based raid is dangerous, and the forums are ABOUND with people who DID and lost all their data. Besides which, the specific issues i highlighted, such as it being slower than OS raid which is much slower than pure hardware is now called scaring people? I even listed the one and only benefit of mobo based raid, you can run windows on a raid array. (such as a raid 0 array for your boot drive).

Do you have a problem with any of the specific ISSUES I listed of hybrid raid? hybrid raid has all the drawbacks of pure hardware and pure software. (except for the ability to boot windows) Can you refute that?

EDIT: ok i forgot another "benefit"... not all editions of windows / macOS allow software RAID. So if you don't run a seperate fileserver, your ONLY choices are likely hybrid and pure hardware, and hybrid is "free"
 

postmortemIA

Diamond Member
Jul 11, 2006
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I haven't tried to reset CMOS myself, why should I?
Really RAID setup is stored on drives itself, that is how Linux is able to use "fakeRAID" how they call it.

With normal use, I don't see more problem than having a single or two drives. I am proof that hybrid RAID works fine for years.

How much hybrid RAID is faster than sing drive it also difficult to measure, most users notice the difference.
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
I haven't tried to reset CMOS myself, why should I?
because often time you have to (or your battery runs out, or you upgrade the firmware) and it makes the array go bye bye... there are ways to recover it, assuming you know exactly the order of the drives and remember the stripe size and don't make any wrong keystrokes. (do you want to clear the array: yes / no, and it starts on yes).

Really RAID setup is stored on drives itself
Problem is, when the cmos gets reset, the mobo sets the controller into IDE mode instead of RAID mode. Which breaks the array, when you switch it back to raid mode it sees multiple broken arrays instead of one array. You have to delete them and build a new array without the initial clearing. plus there are the occasional bugs, etc...

With normal use, I don't see more problem than having a single or two drives. I am proof that hybrid RAID works fine for years.
Go read my post again, please, and pay careful attention to the list of problems and benefits of each.

EDIT: Look... ALL you had to say so far is "I haven't had any trouble"... good for you but pure anecdote. Can you actually go and refute any of my claims instead of saying you had "no problems"?
 

postmortemIA

Diamond Member
Jul 11, 2006
7,721
40
91
Yeah, intel used to provides updates for my board almost on monthly basis, and guess what, every time I did BIOS update it worked fine, no actions needed form my side. Just load new BIOS and that's it. They even included update to RAID firmware on some of these updates.

I have moved form RAID to legacy mode few times, and after switching back it still works. I have even had disconnected drives few times, when you get problem of broken array, once you reconnect all drives, it resumes normal work.

If you don't want to use motherboard RAID, fine, but don't spread false rumors that you haven't witnessed yourself.
 

MerlinRML

Senior member
Sep 9, 2005
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Originally posted by: taltamir
I haven't tried to reset CMOS myself, why should I?
because often time you have to (or your battery runs out, or you upgrade the firmware) and it makes the array go bye bye... there are ways to recover it, assuming you know exactly the order of the drives and remember the stripe size and don't make any wrong keystrokes. (do you want to clear the array: yes / no, and it starts on yes).

Really RAID setup is stored on drives itself
Problem is, when the cmos gets reset, the mobo sets the controller into IDE mode instead of RAID mode. Which breaks the array, when you switch it back to raid mode it sees multiple broken arrays instead of one array. You have to delete them and build a new array without the initial clearing. plus there are the occasional bugs, etc...

I've seen forum posts where people have this problem. The RAID setup is stored completely on the drives, and there's something happening when people boot their system in IDE mode that corrupts the RAID metadata.

While I will not defend motherboard RAID for this behavior as this issue needs to be fixed, I'm curious. Does a hardware RAID controller exhibit the same behavior if one of its drives is connected to the onboard controller in IDE mode and attempted to boot? When the drive is returned, is the RAID metadata corrupt?
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
Originally posted by: postmortemIA
Yeah, intel used to provides updates for my board almost on monthly basis, and guess what, every time I did BIOS update it worked fine, no actions needed form my side. Just load new BIOS and that's it. They even included update to RAID firmware on some of these updates.

I have moved form RAID to legacy mode few times, and after switching back it still works. I have even had disconnected drives few times, when you get problem of broken array, once you reconnect all drives, it resumes normal work.

If you don't want to use motherboard RAID, fine, but don't spread false rumors that you haven't witnessed yourself.

I HAVE witnessed it myself, and so have many others on the board... the guy posting right after you, MerlinRML, has also said he saw it... I don't know what the deal is with you, maybe you were extremely lucky, but your case is the exception.

MerlinRML, pure hardware controller has its own internal system, resetting the CMOS of the mobo intentionally or by accident will not cause such a change. Maybe if you manually change the mode of the hardware raid controller, but AFAIK they are pretty hardy, you don't coincidently lose the array on QUALITY controllers.