Need Help about Raid, format disk, OS, etc..

test2k9

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HI all! I have a few questions...

Okay, I understand that if I were to configure Raid 0, I need at least 2 Hard disks, and if Raid 5, then I need 3 Hard DISKs...

Right now, I have 3 so I want to configure Raid 5, so one of the 3 HDD can be the backup.

The issue is, 2 new HDDs are from same brand (Western Digital, 750GB) and 1 used HDD from Seagate (500GB).

QUESTION 1: If I configure Raid 5, does the OS accepts it even though from different brand, different storage capacity?

QUESTION 2: How do you wire all 3 HDDs ? ( i mean connecting them so BIO can correctly recognizes that I have 3 HDDs. I have 2 SATA cable.

QUESTION 3: How to configure RAID 5 with the Seagate 500GB HDD as backup?

In addition, I know I need to format all 3 and partition.

QUESTION 4: how do you format all 3 (using traditional way at prompt command)?

Lastly, I order Window Vista OS.

QUESTION 5: I'm supposed to format all HDDs, partition, before I install the new OS correct?

Thank you for helping...
 
Answers:

1- Yes and No, the HDD can be from different brand...but not from different storage capacity.

2- You connect all HDD independent, the RAID is configured in the BIOS, not in the mobo. You need 3 SATA cable.

3- How I said in the first answer, you can't configure a RAID 5 with different storage capacity.

4- You can format the 3 HDD one at time, or configure the RAID, and format 2 at same time and the HDD back up of last

5- How I said up, the election is yours. You can also create the partition with the RAID configured, and install the SO at the same time.
 

Paperdoc

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1 - Different brands not a problem. Different sizes is possible, BUT the entire array will be limited to acting as if EVERY drive was only the size of the SMALLEST drive.

2 - Yes, you have to connect all your drives to controller ports on the mobo, so you will need one data cable per drive, plus enough power connectors from your PSU.

3 - No one drive will be the the "The Backup". RAID5 spreads data and checksum / XOR data over all the drives to ensure data redundancy and recovery from single-drive failure.

4 - IF you plan to use the RAID control system built into your motherboard's chipset, you will use those tools to create the RAID5 array before trying to install your OS. That set of tools will establish all the Partitions you need, Format them, and do all the other mysterious things RAID does. When it's done, AND when you install the necessary RAID drivers early in the OS Installation process, your OS will treat the drive as one drive already formatted and ready to use. On the other hand, if you plan to use Windows' own RAID software system, I am not familiar with it but I'm sure you will install to ONE drive first.

5 - See #4. You cannot Format any drive before installing the OS - Format is a command done by the OS. While you can Partition a drive separately using FDISK run under an OS you load and run from a removable drive, it usually is not required. The Install utility on your OS disk will do the Partition and Format operations for you early in the process (or, not necessary if pre-done by your RAID system) before trying to use the disk.
 
Do NOT use the RAID options in Windows. It is not true RAID, it is like a form of disk spanning to simply show all your drives as 1. It has no benefit other than just that, displaying all your drive as 1.
RAID is the very worst form of a "backup" there is. RAID is was designed to improve speed, throughput, storage capacity, and redundacy. It was not designed as a backup. Redundancy and backups are two completely different things.
Just ask the many people who have posted on this forum about their failed RAID array and losing all their data.
 

Paperdoc

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Glad to hear user ratings of the RAID that Windows provides. It kinda confirms my suspicion that what comes free tacked onto the OS is worth every penny!

jitpublisher makes an excellent point. Too many people treat RAID1 or RAID5 or others variants as a backup system, and it is NOT!! Among the various types, RAID5 is often treated as the most fault-tolerant and reliable one (not true, there are higher levels), so it gets abused as a built-in automatic backup substitute. I saw such a system fail and lose all its data! This was in a professionally-run business server system and it ended up with near-simultaneous failures on two drives, which RAID5 cannot fix. Once the array was rebuilt with replacement drives, it took the staff about 3 days, around the clock, to restore all the data from a good backup system. Only a little was lost - the new data from last overnight backup to time of failure. And full recovery was only possible because they had a solid BACKUP SYSTEM that they used faithfully.

OP, I suggest you read up more on what RAID can and cannot do so you understand whether one of them really meets your needs. I also worry that people who don't understand but dive in anyway will not know how to monitor the array, detect problems and repair them before permanent data loss. RAID systems can do a lot of useful stuff to make life easier, but they also are more complex and hence require more thought and attention than a plain hard drive.
 

test2k9

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Thank you to all posters.

It caught up me off guard to know that Raid 1 & 5 are not a reliable backup tool. But it's completely understandable and well aware of. As long as I can save portion of the BACKUP data if one driver fail, it'll be okay because I plan on doing traditional style backup with 3 months or so to a CD/USB external drive. However the reason I'm using Raid 5 is because I already purchased 2 new SATA HDD, and 1 in which my brother gave it to me (Seagate 500GB), so I was force to look at the possibility of configuring Raid 5. Plus I play online game, so maximizing performance is very important.

Anyway just making sure that my steps are correct:

1. install driver (each sata to motherboard, each power to driver)
2. Set Bio to "Raid", boot CD-rom first, etc...
3. configure Raid 5 with partition value
4. insert new OS cd, and then format from OS driver utility correct?

I have another question, can I used the SATA HDD as individual driver storage like IDE HDD?




 

Boxa786

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As all first points have been answered, il start from your recent post.

To setup and install os,

1.connect all 3 drives using sata cables and power leads
2. Set "storage/drives" to raid in bios,
3. Reboot and during bios post you will have the option to go into your motherboard's raid utility (check its manual for this), this is also where you have all the raid options like, again read your motherboard manual for help with the options and how to setup raid 5
- Now that your raid is setup, the rest is just the usual windows install
4. Put windows cd in, boot to cd, if xp you may need the motherboard cd to install sata drivers during load (usually f6)
5. At the start of windows installation, the usual, this is when you partition first, then format, finally install

A. Yes you can simply set the driver as ide and use them as seperate drives, do this in bios, then install windows like you would with an ide drive

B. I would suggest you consider, setting up raid 0 with the new drives and use the free 500gb drive as ide and solely for backing up your important files.

Hope this helps
 



I totally agree with this if you are determined to go RAID.
Set up the 2 alike drives in RAID0, use the third drive as the backup, not part of the array. It is a lot "safer" that way, easier too for someone who is just getting their feet wet with RAID.
You do not need RAID 5.

And to confirm with paperdoc, yes we had a storage server running RAID 0 +1, several years ago. Kind of like RAID 5, but we simply had a set of striped drives mirroring a set of striped drives. Needless to say, yes indeed, for what ever reason still un-beknownst to this day, 2 drives failed at once. We lost everything on the array. Like you, after several days and several technicians later, all was finally restored from our central backup over 3000 miles away. This was a storage tank for several networked Docutechs, and contained many, many, many important customer documents. It could have been a huge disaster had we not had a company wide backup running for all our BDC's around the country.
 

rand_79

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Can use different drive sizes and SHOULD are different things.

Raid 5 is also much slower writing than you would think.
Raid 5 is NOT a performance solution

the only way raid 5 is a performance solution would be with 4 or more drives and that would be for read performance.
and if you had 4 drives it might still be better to go raid 0+1 than raid 5.

not to mention alot of motherboards have very buggy implementations of raid 5.

2 drives in raid 0 are faster than 3 drives in raid 5 anyway.

you would be ahead in the game if you setup the 2 750's as raid 0 install windows etc on it.. then backup important files daily/weekly whatever to the 500gb drive.




that would require you to have 2 drive failures to lose any critical data .

 


--------------------------

What capacity are the HDD?
 

Paperdoc

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I'm still not clear why having three drives pushes you to use a RAID system, but that's a personal choice. If you're decided to use RAID, I agree with the most recent posts. RAID 5 in any form is NOT a performance enhancer - it is really for data security, although NOT a replacement for backups. The only RAID that really does offer some speed-up is RAID0, so use that with your two new 750 GB drives to make your main hard disk array, putting both your Operating system and all your data on it.

The main problem of RAID0 is that it slightly increases the risk of data loss. In RAID0, BOTH disks MUST be working at all times. Any failure in one disk of the array means you have just lost ALL of your data on BOTH of them. So a reliable and fully up-to-date backup system is important to recover from a RAID0 failure. That is why you have received advice above to use the 500 GB as a stand-alone unit for backups AND make sure those backups are frequent - even up to every day!
 

test2k9

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Thank you, I'm going to follow you guys advice and set up the 2 new HDD with Raid 0, and use the old 500GB SATA as separate IDE storage.

But umm, some question to make sure. I have 2 SATA cables which I used to connect the 2 new HDD (750GB), but if I connect the old HDD (500GB), should I get the SATA cable or IDE cable? I suppose I get the Sata cable since my old HDD is SATA, but in bio, just set it as IDE right?

Let me know soon so I can go buy them asap. thanks very much to all
 

Boxa786

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First install the drives, then use your 2 sata cables to connect the two new (750gb) drives, setup raid, then partition and format, finally install windows.

Not sure about how you will have the thrid drive as IDE, but as for installing and the cable, you will need a third sata cable, a sata drive connnects using sata cable no matter what you set it as in bios. So install the third drive, and connect using a third sata cable, to your motherboard, use a spare sata power lead from your power supply unit. You shouldnt need to do anything to this drive, other than (after isntalling windows) setting up the partition and format in windows.

To back your data to the third drive you can either use software like Acronis or simply copy and paste your important files from your raid drives (c:\).
 

Paperdoc

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To avoid confusion, let's distinguish between cable connections and controller settings. If the hard drive physical devices have SATA connectors on them your ONLY choice is to connect to SATA ports on the mobo. Similarly, IDE drives only connect to IDE ports. That's the physical device and its electrical connectors.

Win XP and previous versions had a problem - they did not know "up front" how to deal with any type of hard drive other than PATA or IDE, so they had a decent way to install any extra drivers required during the installation process from a floppy disk. When that became inconvenient, mobo makers offered an alternative in their BIOS - have the BIOS take control of the SATA ports and make them appear to be old-style IDE devices so Win XP had no problems. In the process, the also offer some other options, like using the SATA device connected to the port as a native SATA device, or as an AHCI device, or as a RAID device. All of these have their merits. HOWEVER, as of Vista, the ability to use native SATA and AHCI devices IS included in Windows (as well as older IDE / PATA), so those options in the mobo BIOS can be used with Vista and Win7.

When a BIOS is set to Emulate an IDE or PATA device on a SATA port, it often shows the device in its own screens and displays as an IDE device, even thought it is not, from the hardware view. So don't let that confuse you. In OP's case, ensure the two 750 GB drives are set to be used as RAID devices, but the 500 GB is set either to IDE (or PATA) emulation mode for use with Win XP, or to Native SATA mode for use in Vista. When you actually use the RAID system software to create the RAID0 array, you will designate only those two 750 GB units as parts of the array.

Once you have set up the connections, you also will need to create a way to install the RAID drivers as part of your Windows Install process. First, verify what media can be used as a source of external drivers in whichever version you will be installing. Up to XP they HAD to be on a floppy drive, but Vista may have other alternatives like a USB "drive" or a CD-R or CD-RW. Then you have to put those drivers on that medium. If your mobo came with a CD of software tools (most do), check through the documentation on RAID installations. Usually there is a utility that will write the RAID drivers for your mobo to a disk medium of your choice, and some written (maybe in an electronic file on disk) instructions how to do this and use them.

When the driver disk is ready, you start the process by booting the machine and watch for the screen that allows you to enter the RAID Setup Utilities. Again, read all the documentation with your mobo and its RAID docs so you know how to create your RAID0 array and get it ready to use. You are going to use it to boot from as your C: drive, and it will contain all your OS, your application software, your data - everything. Once the array is created you can turn to OS installation.

When you boot from the Windows Install disk, early on it will ask you if you want to install new drivers, and you must press a key - typically F6 - to do this. Once in that system you will see instructions to insert your removable medium (floppy, USB drive, CD, whatever) that contains the drivers to be installed. You may have more than one driver set to install - follow the instructions of your mobo or RAID system docs. When that is done, Windows will make these new drivers part of its permanent installation for all future use. More importantly, this is how it gets to use that RAID0 array you created as a "Disk" that it can install itself on.
 

mckenzgd

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Lads i'm setting up a system with RAID 5. I have the OS on Sata ide drive and 4 x1tb Drives for the RAID. I already have the OS installed and now i'm setting up the Raid. the RAID in set up in the BIOS and I cant see the RAID in intel storage management system. do i still have to stripe the drives in vista so they can be seen in vista. please note i dont want to reinstall windows.