Our native mobile app has a new name: Fora Communities. Learn more.

What's the best way to setup disk mirroring/raid 1: in bios or in windows?

6506 Views 24 Replies 8 Participants Last post by Bob Sorel, Feb 21, 2014

Schroinx

Discussion Starter · Feb 20, 2014

I want to setup mirrored volumes for the storage disks. It can be done in windows and in bios and on the sil sata controller. What is the difference between them and what is the best way to go about it?

Status: Not open for further replies.

1 - 20 of 25 Posts

ajhieb

· #2 · Feb 20, 2014

Quote:
Originally Posted by Schroinx /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24382508

I want to setup striped volumes for the storage disks. It can be done in windows and in bios and on the sil sata controller. What is the difference between them and what is the best way to go about it?

Striping (RAID-0) is different from Mirroring (RAID-1) but regardless of which you choose, there are pros and cons to doing hardware/bios raid vs software.

If you go with hardware/bios raid, you should be able to boot from the array regardless of what type of array it is. Windows can't boot from a striped array but it can boot from a mirrored one created from within windows.

If you go with a software array, you can move it pretty much any other windows computer and import the array if the need were to arise. With a hardware/bios raid array, you're pretty much confined to similar hardware/chipset if you move the array, and even them I'm not 100% sure that it'll work. (never tried it myself)

Usually, if I'm going with a striped or mirroed array, I'll just use windows to create the array as it seems to work pretty well and their isn't much downside. If you were creating a striped array that you need to boot from, you're pretty much limited to the hardware route.

See less See more

Reactions: 1

Schroinx

Discussion Starter · #3 · Feb 20, 2014

Wups, meant mirrored. I'll try out doing it in windows then. The system drive will not be mirrored.

techmattr

· #4 · Feb 20, 2014

Quote:
Originally Posted by ajhieb /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24382554

Striping (RAID-0) is different from Mirroring (RAID-1) but regardless of which you choose, there are pros and cons to doing hardware/bios raid vs software.

If you go with hardware/bios raid, you should be able to boot from the array regardless of what type of array it is. Windows can't boot from a striped array but it can boot from a mirrored one created from within windows.

If you go with a software array, you can move it pretty much any other windows computer and import the array if the need were to arise. With a hardware/bios raid array, you're pretty much confined to similar hardware/chipset if you move the array, and even them I'm not 100% sure that it'll work. (never tried it myself)

Usually, if I'm going with a striped or mirroed array, I'll just use windows to create the array as it seems to work pretty well and their isn't much downside. If you were creating a striped array that you need to boot from, you're pretty much limited to the hardware route.

The RAID controller on motherboards like the ICH controller are just I/O hubs basically. It actually stands for I/O Controller Hub. They aren't hardware RAID. From a technical standpoint there really is no difference between using Windows or using the onboard. That being said I've always found the Windows RAID to be very unstable while the Intel ICH to be rock solid.

Also,,, I would never count on being able to migrate a RAID volume from one controller to another. Doesn't matter if it's the same card or Windows to Windows. That should NEVER be a part of your strategy. Not saying don't try it if you need to... just don't setup an array with mindset of migrating a RAID volume as a viable failure recovery method. Rely on your backups. Things like FlexRAID/unRAID are a little different on this topic and too much to get into in this thread.

bryansj

· #5 · Feb 20, 2014

I guess the question is why mirror your storage discs? It is a pretty poor backup plan. You'd be better off having the primary storage disc run a backup to the secondary storage disc.

The Windows software mirroring is a real pain to add additional discs as well.

That said I would only choose a software RAID such as FlexRAID/unRAID or a true hardware RAID card, not the built-in or driver based hardware cards. The true RAID cards are in the $500 range and need a battery backup. If you are actually trying to backup data then no RAID is the best choice.

ajhieb

· #6 · Feb 20, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24385969

The RAID controller on motherboards like the ICH controller are just I/O hubs basically. It actually stands for I/O Controller Hub. They aren't hardware RAID. From a technical standpoint there really is no difference between using Windows or using the onboard. That being said I've always found the Windows RAID to be very unstable while the Intel ICH to be rock solid.

Also,,, I would never count on being able to migrate a RAID volume from one controller to another. Doesn't matter if it's the same card or Windows to Windows. That should NEVER be a part of your strategy. Not saying don't try it if you need to... just don't setup an array with mindset of migrating a RAID volume as a viable failure recovery method. Rely on your backups. Things like FlexRAID/unRAID are a little different on this topic and too much to get into in this thread.

I'm aware they aren't the same thing, that's why I listed them individually. For the purpose of this discussion though, they have many similarities which is why I listed them together with said similarities.

I don't really have enough experience with ICH RAID to comment on its overall stability, but I've found Windows RAID to be as stable as the install of Windows is. I've had Windows RAID-0 running on my current box for a few years now with absolutely no problems. I had Windows RAID-1 running on an old server for several years, and the only issues I had with it was a failed drive (not Window's fault) and I was able to replace the drive and re-establish the mirror with 0 downtime. I'd say that pretty much worked as advertised. If you found Windows RAID to be unreliable, I suspect that particular of Windows was unstable to start with.

Moving an array from one controller to another is a perfectly viable option. That is in fact what one would do in the event of a controller failure. Replace the dead controller with a working one. As mentioned above, this typically only works with identical controllers, so you're limited by the availability of said controllers. As far as being able to import Windows arrays, I'm reassured by the fact that if my motherboard goes belly up tonight, that I can replace the board, and have no worries about losing any data (not that I would ever worry much about data on a RAID-0 array anyway) as I know my existing Windows installation, or any other installation will be able to import the array and pick up exactly where I left off. That isn't necessarily the case with hardware/bios RAID.

As far as you insistence on recovering from backup, why recover from backup if the data is perfectly intact? If the drives didn't fail and the array isn't damaged, why restore from backup? It doesn't matter if you reinstall from baremetal, or move the drives to a new machine, the data should still be intact in any situation where one would be importing the array. What benefit is there to restoring from backup vs just importing the array? That makes no sense at all. Just because you have a backup doesn't mean that's the best way to get your data back online.

See less See more

ajhieb

· #7 · Feb 20, 2014

Quote:
Originally Posted by bryansj /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24386166

I guess the question is why mirror your storage discs? It is a pretty poor backup plan. You'd be better off having the primary storage disc run a backup to the secondary storage disc.

The Windows software mirroring is a real pain to add additional discs as well.

That said I would only choose a software RAID such as FlexRAID/unRAID or a true hardware RAID card, not the built-in or driver based hardware cards. The true RAID cards are in the $500 range and need a battery backup. If you are actually trying to backup data then no RAID is the best choice.

I agree that RAID is no replacement for a good backup, but the OP didn't indicate that was his intention. RAID does serve other purposes.

What's your basis for choosing Hardware RAID over software or firmware? It's a necessity for parity based RAID, but from my experience, there isn't a significant difference in performance or reliability between a hardware RAID solution and software/firmware solutions when it comes to RAID-0 or RAID-1. A battery backup is in no way a necessity either. If you are using a hardware RAID controller with onboard cache, you'll need a battery backup, but your risk of data corruption in the event of a power failure is no different with a hardware RAID controller, vs a single drive. If you have write-back caching enabled, you risk losing whatever data is in the write-cache. If you configure the drive(s) for write-thru caching, you don't. Switching to write-thru caching will come at a performance penalty, but that is true of a single drive connected to the motherboard, or an array of drives, connected to a hardware controller.

See less See more

EricN

· #8 · Feb 20, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24385969

Also,,, I would never count on being able to migrate a RAID volume from one controller to another. Doesn't matter if it's the same card or Windows to Windows. That should NEVER be a part of your strategy. Not saying don't try it if you need to... just don't setup an array with mindset of migrating a RAID volume as a viable failure recovery method. Rely on your backups.

Uh, what? Changing controllers is like changing a flat tire. Assuming you know what you are doing and don't select an inappropriate replacement it works just fine.

Reactions: 1

EricN

· #9 · Feb 20, 2014

Quote:
Originally Posted by bryansj /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24386166

I guess the question is why mirror your storage discs? It is a pretty poor backup plan. You'd be better off having the primary storage disc run a backup to the secondary storage disc.

Mirrored storage makes taking a backup extremely fast: just split the mirror. It has the net effect of timeshifting the burden of taking a snapshot. For example, if I have a transactional database that also needs to run reports in the middle of the day during peak load, I can use mirror splitting to suddenly have multiple copies of the data to work from. Then I can wait until non-peak times to resilver the array. Split-Mirror Backup and Restore

For home use, it makes taking an offline backup faster in terms of my time. Fault the drive, pop it out, label it, shelve it, cycle the oldest backup drive into the array, and walk away. The simpler that process is, the more likely I am to actually do it.

roman schepis

· #10 · Feb 21, 2014

I use quantity-3 Three TB Seagate drives. 2 of them RAID 1 mirror and 1 of them as a backup to the mirror. That has provided good performance and was simple to setup. I have not yet found any drawbacks. I use the RAID controller onboard the ASRock Z87 Extreme MB.

techmattr

· #11 · Feb 21, 2014

Quote:
Originally Posted by ajhieb /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24386267

I'm aware they aren't the same thing, that's why I listed them individually. For the purpose of this discussion though, they have many similarities which is why I listed them together with said similarities.

I don't really have enough experience with ICH RAID to comment on its overall stability, but I've found Windows RAID to be as stable as the install of Windows is. I've had Windows RAID-0 running on my current box for a few years now with absolutely no problems. I had Windows RAID-1 running on an old server for several years, and the only issues I had with it was a failed drive (not Window's fault) and I was able to replace the drive and re-establish the mirror with 0 downtime. I'd say that pretty much worked as advertised. If you found Windows RAID to be unreliable, I suspect that particular of Windows was unstable to start with.

Moving an array from one controller to another is a perfectly viable option. That is in fact what one would do in the event of a controller failure. Replace the dead controller with a working one. As mentioned above, this typically only works with identical controllers, so you're limited by the availability of said controllers. As far as being able to import Windows arrays, I'm reassured by the fact that if my motherboard goes belly up tonight, that I can replace the board, and have no worries about losing any data (not that I would ever worry much about data on a RAID-0 array anyway) as I know my existing Windows installation, or any other installation will be able to import the array and pick up exactly where I left off. That isn't necessarily the case with hardware/bios RAID.

As far as you insistence on recovering from backup, why recover from backup if the data is perfectly intact? If the drives didn't fail and the array isn't damaged, why restore from backup? It doesn't matter if you reinstall from baremetal, or move the drives to a new machine, the data should still be intact in any situation where one would be importing the array. What benefit is there to restoring from backup vs just importing the array? That makes no sense at all. Just because you have a backup doesn't mean that's the best way to get your data back online.

Quote:
Originally Posted by EricN /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24386326

Uh, what? Changing controllers is like changing a flat tire. Assuming you know what you are doing and don't select an inappropriate replacement it works just fine.

Neither one of you comprehended my post at all. I chose my words carefully and I stand by them.

ajhieb

· #12 · Feb 21, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24388949

Neither one of you comprehended my post at all. I chose my words carefully and I stand by them.

I comprehended your post just fine.

You made some baseless claims about the stability of Windows RAID without providing any supporting evidence, anecdotal or otherwise.

You went off on some ill-advised tangent about not relying on RAID arrays to be able to migrate from one controller to another without any explanation as to why that would be.

What's not to understand?

See less See more

Aluminum

· #13 · Feb 21, 2014

"Same raid card" is a loaded term:

Migrating hardware raid arrays is only a sane proposition if the firmware versions exactly match. Some are ok if its within the same major patch level, but that is a big gamble.

I'm not even counting cases where you need to make sure the card is the same hardware revision as the previous one, esp w.r.t. OEMs like Dell/HP/etc that like to tweak things and keep the same model name.

In other cases you may need to make sure the card is addressed the same way as the previous install, if it was behind a PCI bridge of some sort and no longer is, or when moving from legacy to UEFI bios, a creek minus the paddle could be in your future.

One nice thing about purely OS-based raid arrays is you can pick them up from one computer to another and change disk controllers and other hardware/firmware configurations completely, the array is an abstract construct. You can potentially change OS versions or even the entire OS at times.

PCH and similar "bios" raid lacks this. Intel only added moving across different RST platforms more recently, and it is very limited.

See less See more

Reactions: 2

techmattr

· #14 · Feb 21, 2014

Quote:
Originally Posted by ajhieb /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24389757

I comprehended your post just fine.

You made some baseless claims about the stability of Windows RAID without providing any supporting evidence, anecdotal or otherwise.

You went off on some ill-advised tangent about not relying on RAID arrays to be able to migrate from one controller to another without any explanation as to why that would be.

What's not to understand?

No actually you didn't.

I corrected your initial statement and then you went on to say "I'm aware they aren't the same thing". I corrected by saying that they ARE the same thing. They are both software RAID. Onboard motherboard RAID controllers are NOT hardware RAID. The hardware is performing NO RAID functions. Software is performing the RAID functions. Hence, software RAID. The fact that you don't know this invalidates anything you have to say on the topic.

Windows RAID is notoriously unstable. Anyone that has been around computers for more than 10 minutes knows this. These aren't MY baseless claims. They are the experience of thousands of people who have been burned by Windows RAID. In addition to that Windows has removed error reporting for RAID synchronization errors in Windows 7/2008+ . So if your RAID1 volume fails to synchronize data and is unable to recover you'll never even know about it unless you check your Disk Management every day. Have fun with that. Every other software RAID provides alerting.

If you think migrating an array from controller to controller is a valid method of failure recovery then you wouldn't last very long in Enterprise IT. I would get fired in a heartbeat if I put that into a disaster recovery document. What do you do if you migrate that RAID volume and the volume is unhealthy? You bend over and lose all your data that's what. This happens more often than it doesn't. Rarely does a raid volume recover from any sort of failure beyond a disk failure. You NEVER, NEVER, NEVER rely on anything other than backups for restoring data. That is basically rule #1 in IT.

See less See more

ajhieb

· #15 · Feb 21, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390114

No actually you didn't.

I corrected your initial statement and then you went on to say "I'm aware they aren't the same thing". I corrected by saying that they ARE the same thing. They are both software RAID. Onboard motherboard RAID controllers are NOT hardware RAID. The hardware is performing NO RAID functions. Software is performing the RAID functions. Hence, software RAID. The fact that you don't know this invalidates anything you have to say on the topic.

You clearly didn't comprehend what I said.

Software RAID isn't the same as Hardware which isn't the same as Firmware. They all have their similarities and they all have their differences. I grouped them by their similarities and explained their differences. A point which you conveniently ignored. That being said, your wrong in your statements about firmware raid.

Your statements would be more accurate in the context of RAID-5, but when talking about RAID-1 or RAID-0 they aren't. The RAID functions (striping and mirroring) are handled by the hardware. That's why the arrays are accessible/viewable from the BIOS, prior to any device drivers being loaded. With RAID-5, parity calculations are offloaded to the host processor via device drivers, but the controller still plays a role in making the RAID work. If the hardware played no roll at all in the RAID functions, you wouldn't need special hardware to do it. All you would need is device drivers written to perform the RAID functionality.

That said, firmware RAID does differ from true Hardware RAID in that it doesn't have an onboard parity engine, and in some cases hardware RAID controllers also offer onboard cache. But that's pretty much the difference.

Quote:
Windows RAID is notoriously unstable. Anyone that has been around computers for more than 10 minutes knows this. These aren't MY baseless claims. They are the experience of thousands of people who have been burned by Windows RAID. In addition to that Windows has removed error reporting for RAID synchronization errors in Windows 7/2008+ . So if your RAID1 volume fails to synchronize data and is unable to recover you'll never even know about it unless you check your Disk Management every day. Have fun with that. Every other software RAID provides alerting.

Now it isn't your baseless claim. But without providing any supporting evidence, indeed, that's exactly what it was. The last time I worked with Windows RAID-1 was with Server 2003, so thanks for the update on the Mirroring issue in 7/2008

Quote:
If you think migrating an array from controller to controller is a valid method of failure recovery then you wouldn't last very long in Enterprise IT. I would get fired in a heartbeat if I put that into a disaster recovery document. What do you do if you migrate that RAID volume and the volume is unhealthy? You bend over and lose all your data that's what. This happens more often than it doesn't. Rarely does a raid volume recover from any sort of failure beyond a disk failure. You NEVER, NEVER, NEVER rely on anything other than backups for restoring data. That is basically rule #1 in IT.

Settle down. NOBODY said that migrating an array was a complete replacement for a backup. That's just ridiculous. It is however a viable option to get a system back online faster in the event of a hardware failure compared to a restore from backup. In the event of a controller failure, you're going to have to replace the controller anyway. What else do you plan on restoring your backup to? Once you have the new controller installed, what's going to get the system online faster: restoring from local (or heaven forbid, offsite) backup? Or migrating the array to the new controller? I'm pretty sure that importing an array is early instantaneous.

If the backup was the primary means for accessing data, it wouldn't be called a backup, it would be called a primary. But it isn't. So as long as my primary data is available to me (and it is after an array migration) that is what I'm going to use. A backup is what I resort to when my primary data isn't available anymore.

And since the whole purpose of RAID is to increase availability, I'm going to presume that availability is a concern to the OP and recommend the solution that gives him the quickest route to getting his data back online.

See less See more

Reactions: 1

techmattr

· #16 · Feb 21, 2014

Quote:
Originally Posted by ajhieb /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390388

You clearly didn't comprehend what I said.

Software RAID isn't the same as Hardware which isn't the same as Firmware.

I corrected your initial statement where you said hardware/bios (onboard) RAID were the same and that is not correct. There's no logic processor so it's not doing any RAID function. The controller BIOS only stores the array configuration. All the ICH does is pass IO to the CPU. That's it. So from a functional standpoint Intel onboard RAID and Windows RAID are identical. Something like a LSISAS2008 will handle the logic for the RAID but still hands off the work to the CPU. Slightly different but still software RAID. Something like a LSISAS2108 based card handles everything. It's a RoC or RAID-on-Chip IC. It's the only form of RAID that should be described as hardware RAID.

EricN

· #17 · Feb 21, 2014

Quote:
Originally Posted by ajhieb /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390388

That said, firmware RAID does differ from true Hardware RAID in that it doesn't have an onboard parity engine, and in some cases hardware RAID controllers also offer onboard cache. But that's pretty much the difference.
Now it isn't your baseless claim. But without providing any supporting evidence, indeed, that's exactly what it was. The last time I worked with Windows RAID-1 was with Server 2003, so thanks for the update on the Mirroring issue in 7/2008

Actually, it's still a baseless claim. Microsoft migrated all that reporting to System Center. They are complaining about not getting a visual warning on the local client.

techmattr

· #18 · Feb 21, 2014

Quote:
Originally Posted by EricN /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390470

Actually, it's still a baseless claim. Microsoft migrated all that reporting to System Center. They are complaining about not getting a visual warning on the local client.

So purchasing software that costs thousands of dollars, requires an additional server to setup, just to manage your home RAID array or even simple non critical data arrays is a logical choice? You have an irrational view of baseless.

Bottom line is for a home user there is no way of knowing your array has failed other than manually checking.

EricN

· #19 · Feb 21, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390485

So purchasing software that costs thousands of dollars, requires an additional server to setup, just to manage your home RAID array or even simple non critical data arrays is a logical choice? You have an irrational view of baseless.

Bottom line is for a home user there is no way of knowing your array has failed other than manually checking.

System Center Essentials 2007 cost $99, and SCE 2010 cost $125. Neither required a separate server.

Also, all systems require manual log checking or configuring push notifications (i.e. email/sms). A systray warning on the desktop still requires manually checking it. Unless your storage server is doubling as your primary desktop, a popup isn't going to help.

No way for a home user to know? Use Powershell and Windows Scheduler to email yourself when you have a failure.

ajhieb

· #20 · Feb 21, 2014

Quote:
Originally Posted by techmattr /t/1518844/whats-the-best-way-to-setup-disk-mirroring-raid-1-in-bios-or-in-windows#post_24390469

I corrected your initial statement where you said hardware/bios (onboard) RAID were the same and that is not correct.

I said no such thing. Stop attributing things to me that I never said.

What I did say is that hardware/bios RAID have similarities (and distinct differences when compared to software RAID) Which is accurate, and I stand by that statement.

Quote:
here's no logic processor so it's not doing any RAID function. The controller BIOS only stores the array configuration.

That is patently false. A dedicated logic processor serves no purpose for RAID-1 or RAID-0. A lack of said processor in no way prohibits a RAID controller from striping or mirroring drives.

Quote:
All the ICH does is pass IO to the CPU. That's it. So from a functional standpoint Intel onboard RAID and Windows RAID are identical.

Functionally, they are most certainly not identical. With ICH RAID I can create a bootable RAID-0 array. Windows can't. I can move a Windows array to any other Windows machine. That isn't possible with ICH RAID.

Quote:
Something like a LSISAS2008 will handle the logic for the RAID but still hands off the work to the CPU. Slightly different but still software RAID. Something like a LSISAS2108 based card handles everything. It's a RoC or RAID-on-Chip IC. It's the only form of RAID that should be described as hardware RAID.

Software RAID, by definition is hardware independent. It runs on the OS layer (or on top of it). Firmware/BIOS/ICH RAID is inextricably tied to the hardware which makes it inherently different from software RAID. The rest of the world acknowledges this difference. If you choose not to, that's no you, but there most definitely is a difference, in general, and in the context of this conversation, between Software RAID and Firmware RAID.

As stated above, all of the RAID variations have similarities, but they also hive differences... that's why people bother to distinguish them in the first place.

See less See more

1 - 20 of 25 Posts

Status: Not open for further replies.