RAID Trust Issues — Windows Or a Cheap Controller? 564
NicApicella writes "My new system has two sparklin' SATA drives which I would like to mirror. After having been burned by a not-so-cheap, dedicated RAID controller, I have been pointed to software RAID solutions. I now stand in front of two choices for setting up my RAID: a Windows 7 RC software RAID or a hardware RAID done by the cheap integrated RAID controller of my motherboard. Based on past experiences, I have decided that only my data is worth saving — that's why the RAID should mirror two disks (FAT32) that are not the boot disk (i.e. do not contain an OS or any fancy stuff). Of course, such a setup should secure my data; should a drive crash, I want the system up and running in no time. Even more importantly, I want any drive and its data to be as safe and portable as possible (that's the reason for choosing FAT32), even if the OS or the controller screw up big time. So, which should I choose? Who should I trust more, Microsoft's Windows 7 or possibly the cheapest RAID controller on the market? Are there other cheap solutions?"
Comment removed (Score:5, Insightful)
FAT??? (Score:5, Insightful)
You data is most important and you plan to use FAT? Good luck with that!
Seriously, though. No RAID solution that is not totally S/W is portable. But do you really need RAID? It sounds like what you need is a good backup solution with frequent backups. Does you data change so much that losing one day's worth of data would be a problem?
RAID != BACKUP (Score:5, Insightful)
RAID is *NOT* backup! (Score:5, Insightful)
RAID is never about protection. (Score:4, Insightful)
Off site backup and test your restores (Score:3, Insightful)
Without regard to if you use software or hardware RAID or the quality of the RAID system, RAID only protects you from a physical disk failure. If you as a user screw up (delete or change something you didn't want to) or if some software bug screws up for you, or if you have a non-disk related hardware failure (causing a data corrupting machine crash) then you have lost your data -- RAID doesn't help.
Even if you are only trying to protect against disk errors, if the RAID system fails (even expensive quality ones can), or if you don't know and follow the recovery procedures EXACTLY, you can lose all your data.
The only reliable solution is making a copy or a "backup". Backup does not mean making a copy of the data on the same machine. (Whatever took out your RAID might also take out the other non-RAID disk or directory that you put your copy on.) If you are paranoid (or just prudent) your backup should not be a mapped or mounted drive on another machine. (Viruses can write to the network as well.)
And finally... Backups only count if you have tested your restore process.
You are asking the wrong question. (Score:5, Insightful)
RAID is only marginally valuable. In my experience, for all but the most carefully controlled environments, RAID simply adds complexity, the number of things to go wrong increases, along with the likelyhood of lost data. Do it only if you want the *experience* of running RAID, but don't count on RAID to "save your data".
I've worked as a system administrator for more than a decade, in medium-large scale deployments with good success, (think: servicing thousands of users, hundreds of domain names, tens of thousands of email addresses, etc) so I think I have some useful experience you can benefit from.
IMHO, you most likely to lose data from the following things (in order)
1) Aw sh1tz. "I didn't mean to delete that folder"... or "Whoops! I formatted the wrong drive", "I saved the wrong version of the file!", whatever. Although I *myself* don't have this happen often, it does happen. And even in my case I've lost about as much useful information this way as by drives dying. Users delete stuff all the time, and it's usually my job to bring it back, which is why I perform redundant, historical backups EVERY SINGLE DAY.
2) Malware. Don't minimize this - it's real, and it's why I reply to Parent. You are more likely to lose information from a virus/worm/malware and/or b0rked install of something that hoses your filesystem than by a hard disk crash given stable hardware.
3) Bugs. Filesystems have bugs. So do applications, utilities, anything with software. Strange, unexpected conditions, often caused by bugs in applications can cause data to "disappear", files to get corrupted, filesystems to get corrupted, folders to be incompletely written, etc. This is about as likely to cause lost data as:
4) Hardware failure. This is one of the lowest orders of lost data, although when it happens, it can be one of the most extreme.
Let me say this: RAID 1/5 only PARTIALLY protects you from the last one. Actual, bona-fide backups protect you from all of these. If you care about the data, get backups. If you care about uptimes at great expense, RAID *may* be worth it.
My advice is something most people don't want to hear: for personal use, get backups online for $5/month. Mozy/Carbonite/etc. There are zillion vendors, just Google it. In two years, it will cost you about as much as that 2nd hard drive. It protects you far better than that 2nd hard drive, and it's so automatic that you'll hardly notice it until the moment it actually matters: when you just have discovered that your data is gone.
Re:Seriously? (Score:5, Insightful)
The article smacks of false dichotomy. There are a number of solutions, not just Windows 7 or a hardware RAID controller.
To begin with, every NT-lineage Windows version ever produced supports software RAID out of the box. Add that to the fact that any major Linux distro today supports software RAID. And so do the *BSDs. And Mac OS X. And Solaris. And probably a bunch of other platforms I can't think of right now.
Hell, you could buy one of these one of these [linksysbycisco.com] and throw the drives in it, connect it to your network switch, and presto -- instant RAID+NAS.
I think we would all like to know why you think Windows 7 is your only option, because if that's what you think, you don't know how mistaken you are.
Are sure RAID is what you want? (Score:3, Insightful)
With RAID mirroring, if you overwrite or delete an important file, it's copy on the mirror is immediately overwritten/deleted too, and the file is lost. Wouldn't you rather need a good regular backup?
And as someone pointed out already, FAT is really not a reliable file system. If you are on Windows, use NTFS. It is still portable, having read/write drivers for both Linux and Mac (see this guide [alma.ch]).
Since the files you want to keep safe appear to be regular files, not system files, any simple file copy mechanism could do. For an easy and simple system, you can use the Windows robocopy.exe tool in a batch file. For a more sophisticated system which can keep older file versions, and can easily be adapted for use over the network, you could try a Windows version of rsync like cwrsync. There are also a few rsync GUI frontends for Windows.
If you decide you really want RAID mirroring and go with the hardware solution, my understanding is that you need a replacement controller in case yours breaks. Since your controller seems to be embedded in the motherboard, you would need a replacement motherboard.
With the Windows software RAID, you are dependent on that software, and have portability only between machines with this Windows 7 software RAID (possibly even only this particular version).
Re:FAT??? (Score:4, Insightful)
If all you want is multiple copies of your data, then really what you want is an automated incremental backup system, that copies your files to a second hard drive, and ideally keeps a few older copies so that if a file gets accidentally deleted or somehow corrupted, you have a chance to go back and find a usable copy. This is what I do on my system: I keep multiple incremental copies from the last few days/weeks/months. It was easy to set-up (in Linux, mind you). Do hourly syncs if necessary.
Also critical, if the poster is truly concerned about never losing data, is to get some kind of offsite backup. Two hard drives don't do you much good when the computer is stolen or your roof leaks. You need to have a way to regularly copy data offsite (ideally automated over the network, or via external hard drive if you're sufficiently disciplined).
RAID has its uses, to be sure. But if the poster is most worried about never losing important user files, then it seems like what he wants is is the multiple-redundancy of backup, not the immediate failover of RAID.
Re:Seriously? (Score:3, Insightful)
The article smacks of false dichotomy. There are a number of solutions, not just Windows 7 or a hardware RAID controller.
Agreed.
As I see it, if you want guaranteed repairability then you basically have two options: enterprise-class hardware with a support contract (and price tag to match), or an Open Source software solution.
Put another way, either you pay someone to take responsibility for fixing it, or you take responsibility yourself. A Microsoft solution doesn't give you enough control to take full responsibility, because you can't be certain that it will be legally or technically possible to recreate your current setup in five years time.
Re:You are asking the wrong question. (Score:5, Insightful)
Your 4 points are correct. However, the reason for using RAID is NOT as a backup. RAID != Backup.
RAID is for redundancy and performance increases.
I had a drive die in my NAS a few weeks ago. It took 5 minutes to walk to the server room and plug in a new drive. There's no added complexity for the sysadmin, everything is done automagically by the RAID controller. Losing a server or data for hours while the drive is restored from tape is more expensive and complex.
Re:You are asking the wrong question. (Score:2, Insightful)
... you'll hardly notice it until the moment it actually matters: when you just have discovered that your data is gone.
Or until the backup company disappears. I suspect hardware is much more stable than any company providing any online backup.
I'd feel safer by far with an outfit that picks up your physical tapes and can return them as needed. If the company is going belly up, it's a lot harder for them to "lose" a warehouseful of tapes than a bunch of files on rotating memory.
For a private person interested in backup, find a safe, offsite place for your backup. Take at-home backups to work. If you have a small business, take the work tapes home.
Re:You are asking the wrong question. (Score:3, Insightful)
My advice is something most people don't want to hear: for personal use, get backups online for $5/month. Mozy/Carbonite/etc. There are zillion vendors, just Google it. In two years, it will cost you about as much as that 2nd hard drive. It protects you far better than that 2nd hard drive, and it's so automatic that you'll hardly notice it until the moment it actually matters: when you just have discovered that your data is gone.
And is so slow that a LS120 drive reading a 1.44MB floppy would actually be faster. Or a 1x CROM. Or a 16 year old hard drive.
Also, I have to trust that the service and my internet connection will be available when I need to restore my data.
Or I can use RAID... and tapes.
Re: online backups (Score:5, Insightful)
Personally, I haven't yet encountered anyone who really got benefit from those personal Internet backup services like Mozy. In regular use, it always seems like the person exceeds their storage allotment or Internet connectivity issues prevent them from recovering what they need, when they need it.
I tend to recommend people buy an inexpensive external USB or firewire drive, leave it attached and assigned as a backup device, and have some software package run a daily backup of all the relevant folders and files they might need to save.
It's great that your data is stored offline and off-site ... but I'm just not sold on most of the implementations for "home use" being as great a solution as they first appear to be. Many of the providers have come and gone over the years, too. What happens when your offline backup company goes under?
Re:Seriously? (Score:2, Insightful)
To begin with, every NT-lineage Windows version ever produced supports software RAID out of the box.
I'm sitting in front of a copy of Vista Ultimate right here that doesn't. Do you have a citation or anything? Or are you using some alternate use of the word "supports" that doesn't mean "supported by Microsoft?"
Re:You are asking the wrong question. (Score:5, Insightful)
Re:Are you crazy? (Score:3, Insightful)
No, I don't work for any of these. And I do maintain my own backup set, because I backup TBs of data daily. But for personal use, the online vendors are the best bet.
Re:RAID != BACKUP (Score:3, Insightful)
What about Volume Shadow Copy in Winblows or Time Machine in OSX? They seem pretty useful in the "man, that was dumb" scenarios.
Buy more drives! (Score:3, Insightful)
Simple answer: buy more drives. Put the extras in the closet. By the time you run out of spares, it will be time to move on to new drives.
Re:Just remember the first rule of RAID 0 (Score:2, Insightful)
Re:On board all the way!! (Score:2, Insightful)
Again, if you need a stable parts supply, don't go with a whitebox server. Software RAID doesn't help you in that regard - instead of an 8 year old SAS RAID controller you'll be looking for a generic 8 year old SAS controller. It'll still be shitty and not usuable in a production environment.
Re:RAID is never about protection. (Score:3, Insightful)
Tell me, how often do you back up your data? Daily? Hourly? Because when your hard disk craps out after a morning's work you'll be mighty grateful for that RAID-1 mirror.
Re:You are asking the wrong question. (Score:3, Insightful)
5) Theft. Break-ins do happen and no amount of RAID will protect your data from that.
buy two external drives; one is always offsite (Score:1, Insightful)
I tend to recommend people buy an inexpensive external USB or firewire drive, leave it attached and assigned as a backup device, and have some software package run a daily backup of all the relevant folders and files they might need to save.
Buy two drives.
Every Monday take one to work (make sure your name is on it) and bring back the one you had at work and hook it up to your system. This way if there's a power surge or fire at least one set is offsite.
A backup isn't really a backup unless it's offline (and preferably there's also an offsite).
Hope for the best, but be prepared for the worst.
Re:You are asking the wrong question. (Score:3, Insightful)
I had a similar case where the controller decided it wanted to die and started writing spurious data to the disks. RAID won't protect you from the controller itself dying - and that also can occur for software RAID as well, the controller can still bork your data.
Re:You are asking the wrong question. (Score:2, Insightful)
Re:You are asking the wrong question. (Score:4, Insightful)
WE KNOW RAID ISNT A BACKUP, NOW SHUT UP (Score:1, Insightful)
Amazing, all these posts and hardly anyone actulay answered his question. Frankly these people who say raid isnt a replacement for backups should just shut the hell up already. The reason people use raid as in mirroring is just for redundacy, and for that purpose it works well. Regardless of what people have been saying about how useless it is I cant say I ever saw a mirrored array fail in a way to lose data when the whole system was fried, talking about file system errors and mailware causing you to lose data is like not driving because you might get carjacked.
Also what is with the people recomending using 2 identical drives? I have seen failues on arrays like that where one will die and then a few hours/days later the identical disk will die as well. Its better to have at least 2 different models so that if you bought a bad run when you got your drives, they wont all die close together.
But to ACTULAY ANSWER HIS QUESTION...
I have never had an issue with a onboard controler. Unless your planning on having a large array instead of a mirror it should be just fine.
Re:Just remember the first rule of RAID 0 (Score:5, Insightful)
Raids work best when every disk in the array is the same model and revision. If you plan to build a 5 disk raid array you should also purchase a 6th drive to keep as a cold spare.
I hate to break it to you, but you're actually wrong.
A RAID array is most effective using completely different drives, but of the same capacity. Five hard disks from the same manufacturer, of the same model, bought at the same time means that you're highly likely to get five drives from the same batch. Let's posit that there was some defect in this batch. Now all five of your drives have a significantly higher probability of failing at the same time. Oops! RAID can only deal with one (or two) drive failures!
Using drives from different manufacturers or model lines means you spread the risk of simultaneous drive failure.
Re:Are you crazy? (Score:2, Insightful)
My hackles go up anytime I hear or read things like this. I know people who have had bad experiences with a single piece of hardware from a specific manufacturer and never use that brand again. They tell people that the brand is "crap" or "worthless" based on a single piece of data, namely, the failure of a single device from that manufacturer.
As an example, I have a friend who purchased a Maxtor SATA hard drive several years back. It died on him less than 2 months after he got it. He threw it away and refused to purchase any more Maxtor hard drives. If he had sent the drive in for warranty replacement, and that one had failed in much the same way, I might put more stock in what he says.
I've had bad experiences with many brands of hardware. But I rarely have a consistent problem. A few years back, it was time to start replacing our company laptops. As we had a contract with Dell, I purchased several Latitude D620's and D630's. Over the course of the next year, all of the hard drives suffered the same type of hardware failure without exception. In most cases, nothing was lost. But as the other Admins can attest to, there are always one or two people who refuse to backup the work they do at home, and in those cases, quite a bit of information was lost.
Because Dell continued to use the same brand of hard drives in their laptops, this year, we switched to HP laptops. I didn't make the switch because of one isolated event. And I certainly don't tell people that Dell laptops are crap because of my experience. But as a Network Admin, my primary responsibility is the safety of the data that my company requires for operation. It would be derelict of me to continue purchasing a model of laptop with a proven track record of hard drive failure.
I personally use Western Digital hard drives. I have not had any "bad" or discouraging experiences with the hard drives I've bought over the years from WD. However, I have also not had any of those issues with the Maxtor or Seagate hard drives that I have had over the years. Maybe I am lucky. Who knows.
In reality, you can never assess the quality of a manufactured item based on one sample because there is no such thing as a perfect manufacturing process. And even if there was, there would still be human beings involved in the process at some point. Even robots are not perfect and mess things up from time to time.
Re:FAT??? (Score:3, Insightful)
"Most users _never_ read their event log, so logging the failure like this is next to useless."
The original complaint was that Windows doesn't report disk errors, which is not true. If this were Linux, people would point out that the information desired is right there in the logs..
Software RAID isn't (wasn't?) even available on consumer desktop versions of Windows, so you'd expect some minimum level of cluefulness on the part of the user and less handholding on the part of Microsoft.
A.