what is raid 1 2 3 4 5 6 etc...?
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RAID (redundant array of independent disks; originally redundant array of inexpensive disks) is a way of storing the same data in different places (thus, redundantly) on multiple hard disks. By placing data on multiple disks, I/O (input/output) operations can overlap in a balanced way, improving performance. Since multiple disks increases the mean time between failures (MTBF), storing data redundantly also increases fault tolerance. \nA RAID appears to the operating system to be a single logical hard disk. RAID employs the technique of disk striping, which involves partitioning each drive's storage space into units ranging from a sector (512 bytes) up to several megabytes. The stripes of all the disks are interleaved and addressed in order. \n\nIn a single-user system where large records, such as medical or other scientific images, are stored, the stripes are typically set up to be small (perhaps 512 bytes) so that a single record spans all disks and can be accessed quickly by reading all disks at the same time. \n\nIn a multi-user system, better performance requires establishing a stripe wide enough to hold the typical or maximum size record. This allows overlapped disk I/O across drives. \n\nThere are at least nine types of RAID plus a non-redundant array (RAID-0): \n\nRAID-0: This technique has striping but no redundancy of data. It offers the best performance but no fault-tolerance. \nRAID-1: This type is also known as disk mirroring and consists of at least two drives that duplicate the storage of data. There is no striping. Read performance is improved since either disk can be read at the same time. Write performance is the same as for single disk storage. RAID-1 provides the best performance and the best fault-tolerance in a multi-user system. \nRAID-2: This type uses striping across disks with some disks storing error checking and correcting (ECC) information. It has no advantage over RAID-3. \nRAID-3: This type uses striping and dedicates one drive to storing parity information. The embedded error checking (ECC) information is used to detect errors. Data recovery is accomplished by calculating the exclusive OR (XOR) of the information recorded on the other drives. Since an I/O operation addresses all drives at the same time, RAID-3 cannot overlap I/O. For this reason, RAID-3 is best for single-user systems with long record applications. \nRAID-4: This type uses large stripes, which means you can read records from any single drive. This allows you to take advantage of overlapped I/O for read operations. Since all write operations have to update the parity drive, no I/O overlapping is possible. RAID-4 offers no advantage over RAID-5. \nRAID-5: This type includes a rotating parity array, thus addressing the write limitation in RAID-4. Thus, all read and write operations can be overlapped. RAID-5 stores parity information but not redundant data (but parity information can be used to reconstruct data). RAID-5 requires at least three and usually five disks for the array. It's best for multi-user systems in which performance is not critical or which do few write operations. \nRAID-6: This type is similar to RAID-5 but includes a second parity scheme that is distributed across different drives and thus offers extremely high fault- and drive-failure tolerance. \nRAID-7: This type includes a real-time embedded operating system as a controller, caching via a high-speed bus, and other characteristics of a stand-alone computer. One vendor offers this system. \nRAID-10: Combining RAID-0 and RAID-1 is often referred to as RAID-10, which offers higher performance than RAID-1 but at much higher cost. There are two subtypes: In RAID-0+1, data is organized as stripes across multiple disks, and then the striped disk sets are mirrored. In RAID-1+0, the data is mirrored and the mirrors are striped. \nRAID-50 (or RAID-5+0): This type consists of a series of RAID-5 groups and striped in RAID-0 fashion to improve RAID-5 performance wi
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depends on the database, depends on the part of the database.  Depends also on \nwho you ask :-)\nHere is what I like (raid 0 = stripes, raid 1 = mirrors, raid 5 = \nstriping+parity):\n-->no raid, raid 0 or raid 0+1 for online redo logs AND control files.  \nYou should still let us multiplex them ourselves even if you mirror \nthem.  We have more opportunities for failure if the raid subsystem reports a \n"warning" back to us -- if we have multiplexed them -- we are OK with that.\n-->no raid or raid 0 for temporary datafiles (used with temporary \ntablespaces).  no raid/raid 0 is sufficient.  If you lose these, who cares?  You \nwant speed on these, not reliability.  If a disk fails, drop and recreate temp \nelsewhere.\n-->no raid, raid 0 or raid 0+1 for archive.  Again, let us multiplex if you \nuse no raid or raid 0, let the OS do it (different from online redo log here) if \nyou use 0+1.\n-->raid 0+1 for rollback.  It get written to lots.  It is important to have \nprotected.  We cannot multiplex them so let the OS do it.  Use this for \ndatafiles you believe will be HEAVILY written.  Bear in mind, we buffer writes \nto datafiles, they happen in the background so the poor write performance of \nraid 5 is usually OK except for the heavily written files (such as rollback).\n-->raid 5 (unless you can do raid 0+1 for all of course) for datafiles that \nexperience what you determine to be "medium" or "moderate" write activity.  \nSince this happens in the background typcially (not with direct path loads and \nsuch) -- raid 5 can typically be safely used with these.  As these files \nrepresent the BULK of your database and the above represent the smaller part -- \nyou achieve most of the cost saving without impacting performance too much.\n\nTry to dedicate specific devices to \n\n-online redo\n-archive\n-temp\n\nthey should not have to share their devices with others in a "perfect" world \n(even with eachother).\n\n\nPlease also check the information in the following weblink\n\nhttp://office.microsoft.com/en-au/assistance/ha011727121033.aspx
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The answer depends.  If you have two hard drives in your computer that are the exact same size (i.e. both 80 gigs) you should choose raid and configure your system in a raid 1 format.  What this does is basically give you a fail safe if one hard drive crashes.  \n\nIf you only have one hard drive in the computer I would  choose IDE, raid would serve no purpose.
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8 bits =1 byte\n1024 bytes=1 kb\n1024 kb= 1mb\n1024 mb= 1gb\n1024 gb= 1tb(tera byte)
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THERE PRETTY CLOSE ON SOME BENCHMARKS GO WITH ONE RAP ONE SATA RAID 1 IF U DONT GAME GO WITH ATHLON X2 GREAT CHIP I HAVE 4200 BUT THEY HAVE 3800 CLOSE TOO THE SAME PRICE AS YOUR 3700 AT NEWEGG.COM
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Nope, if windows XP doesnt recognise the raid you will need to d/ownload the drives. If you don't have the drivers windows will not recognise teh drive. You need to do a search on google for the Sata drivers, if its on board try looking on the Motherboards manfacturers website.
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RAID 1\nA RAID 1 creates an exact copy (or mirror) of a set of data on two or more disks. This is useful when read performance is more important than minimizing the storage capacity used for redundancy. The array can only be as big as the smallest member disk, however. A classic RAID 1 mirrored pair contains two disks, which increases reliability by a factor of two over a single disk, but it is possible to have many more than two copies. Since each member can be addressed independently if the other fails, reliability is a linear multiple of the number of members. To truly get the full redundancy benefits of RAID 1, independent disk controllers are recommended, one for each disk. Some refer to this practice as splitting or duplexing.\n\nWhen reading, both disks can be accessed independently. Like RAID 0 the average seek time is reduced by half when randomly reading but because each disk has the exact same data the requested sectors can always be split evenly between the disks and the seek time remains low. The transfer rate would also be doubled. For three disks the seek time would be a third and the transfer rate would be tripled. The only limit is how many disks can be connected to the controller and its maximum transfer speed. Many older IDE RAID 1 cards read from one disk in the pair, so their read performance is that of a single disk. Some older RAID 1 implementations would also read both disks simultaneously and compare the data to catch errors. The error detection and correction on modern disks makes this less useful in environments requiring normal commercial availability. When writing, the array performs like a single disk as all mirrors must be written with the data.\n\nRAID 1 has many administrative advantages. For instance, in some 365*24 environments, it is possible to "Split the Mirror": declare one disk as inactive, do a backup of that disk, and then "rebuild" the mirror. This requires that the application support recovery from the image of data on the disk at the point of the mirror split. This procedure is less critical in the presence of the "snapshot" feature of some filesystems, in which some space is reserved for changes, presenting a static point-in-time view of the filesystem. Alternatively, a set of disks can be kept in much the same way as traditional backup tapes are.\n\nAlso, one common practice is to create an extra mirror of a volume (also known as a Business Continuance Volume or BCV) which is meant to be split from the source RAID set and used independently. In some implementations, these extra mirrors can be split and then incrementally re-established, instead of requiring a complete RAID set rebuild.\n\n Traditional\n   RAID 1\nA1        A1\nA2        A2\nA3        A3\nA4        A4\n\nNote: A1, A2, et cetera each represent one data block; each column represents one disk.\n\n\nRAID 2\nA RAID 2 stripes data at the bit (rather than block) level, and uses a Hamming code for error correction. The disks are synchronized by the controller to run in perfect tandem. This is the only original level of RAID that is not currently used. Extremely high data transfer rates are possible.\n\n\nRAID 3\nA RAID 3 uses byte-level striping with a dedicated parity disk. RAID 3 is very rare in practice. One of the side effects of RAID 3 is that it generally cannot service multiple requests simultaneously. This comes about because any single block of data will by definition be spread across all members of the set and will reside in the same location, so any I/O operation requires activity on every disk.\n\nIn our example below, a request for block "A" consisting of bytes A1-A9, would require all three data disks to seek to the beginning(A1) and reply with their contents. A simultaneous request for block B would have to wait.\n\n  Traditional\n    RAID 3\nA1  A2  A3  Ap(1-3)\nA4  A5  A6  Ap(4-6)\nA7  A8  A9  Ap(7-9)\nB1  B2  B3  Bp(1-3)\n\nNote: A1, B1, etcetera each represent one
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1bit= 0 or 1\n1byte=8 bit\n1Kilobyte=1024 Byte\n1 Mega Byte= 1024 Kilo Byte\n1 Giga byte= 1024 Mega byte\n1 Tera Byte=1024 Giga Byte\n1 Googlebyte=1 share of Google stock\n1 Bubbabyte= 1 piece of bubalicious\n1 lovebyte= a hickey\n1 trilobyte= An extinct crustacean\n1 voteabyte= 10 points for my wit! (thanx)
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Medic was right, except he/she didn't realize you are trying to run IDE raid with two different IDE controllers.  You can't do that.  If your motherboard doesn't support IDE RAID, then you are going to have to use both hard drives through the PCI IDE controller, assuming it's RAID capable.  If it isn't, I'd go with 4 SATA drives.
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Look at the old hard drive.  There should be a label with the model number and manufacturer on it.  Search the model number at the manufacturer's web site.  It should tell you which kind of hard drive it it.\n\nTypically, it depends on what connector is on it.  A small connector which is about a little over half an inch is a serial ata connector.  A larger connector about 2 inches wide is a ata/uata/dma/udma/ide connector.  Each of these different modes are different transfer speeds, but plug looks the same.  By researching your model at the manufacturer's site will tell you what speed it will transfer at, thus giving you the right protocol hard drive to purchase.  \n\nfor example,\nultra 33 - theoretical 33 MHz transfer\nultra 66 - theoretical 66 MHz transfer\nultra 100 - theoretical 100 MHz transfer\nultra 133 - theoretical 133 MHz transfer\nsata 150 - theoretical 150 MHz transfer\n\nThere are also SCSI drives, but most mainstream home computers don't have them.\n\nHard drives don't come in RAID form, it is how how you set up your hard drives if your motherboard/host adapter supports RAID.  RAID is an array of hard drives.  You can use multiple hard drives in RAID to get effects such as combined output from multiple hard drives for more output speed, or for redundancy such as writing to two hard drives at once so you have an extra hard drive with with same data for backup in case one happens to die. More advanced versions of RAID can do both of these functions (combined output and redundancy) at the same time.
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In My Computer.  Select: Local Disk (C).  View DETAILS, lower left. \nClick on View System Information at the top for the other info.  \n\nClick this link for the kilobyte/megabyte values you requested:\nhttp://familyinternet.about.com/cs/computinghelp/l/aa052401a.htm\n\nHope that helps.
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Get the 500gb (7200rpm) serial ata hard drive with 8mb databurst cache.\n\nRAID 0 means that two or more hard drives have been combined and made to appear like 1 hard drive.  The problem is that if a hard drive has a 1 in 100 chance of failing, then a RAID 0 with 2 drives has a 1 in 50 chance of failing.  With a RAID 0, if any drive in fails that's part of the RAID 0, then you lose EVERYTHING on BOTH drives.\n\nRAID 0's are faster than single drives, but if this is an external drive using USB 2, then the limitation is the USB connection and a RAID 0 isn't going to be of much help.\n--------------------------------------------\nSo far, few people understand RAID 0.  RAID 1 is a mirror where the data is stored simultaneously on two hard drives so in case 1 fails, you have a backup.  RAID 0 is NOT a mirror - it's not TECHNICALLY a RAID (RAID stands for "Redundant Array of Inexpensive Disks).  There is NO redundancy in a RAID 0, which is why people who understand RAID understand why RAID 0 is NOT a true RAID - again, if either drive fails, you lose ALL your data on both drives.  \n\nThink of it like this: a RAID 0 is like having two books, book 1 has all the odd pages, book 2 has all the even pages.  If you lose either book, you no longer have a coherent story.  That's how RAID works - each drive gets one "page" of information... if one drive fails (one book is lost) then your files are corrupt and cannot be recovered.
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It depends on if you have a scsi narrow or scsi wide device.  If you have a scsi narrow device jumpers 1-3 will assign an id and jumper 4 will usually be used to enable parity or disable it.  If the device is scsi wide than each jumper will represent a binary number.  I'll assume it's a scsi wide device because narrow is usually on really old machines.  Basically you have to look at the jumpers in binary. Jumper 1=1 Jumper 2=2 jumper 3=4 jumper 4=8.  You just add together the numbers to reach the scsi ID.    Your scsi id range for a narrow device is 0 through 15 which gives you a total of 16 unique ID's for that scsi bus.  So in your example you have jumper 2 on which equals 2 and jumper 3 on which equals 4.  2+4=6 so the scsi id would be 6.  No jumpers at all would give you scsi id 0.  I usually reserve zero for boot up drives.
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Closest I can think of is .ddap, which is the extension used by Appples disk doubler routine on the mac
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USB drive\nFlash Drive\nHard Drive\nCD \nDVD
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RAID stands for Redundant Array of Independent Disks. this is used to improve the performance of a system. there are many RAID levels. RAID 0 to RAID 6. each level has a different approach to improve the performance. \nfor example in RAID 0, disk mirroring is done. mirroring is nothing but creating duplicate copies of the disks. this increases reliability because we can refer to the duplicate copy in case of a system crash, but it considerably decreases the speed.\n\nin other RAID levels, we have "stripping" which is removing redundant data. stripping can be done at bit level, which is called bit level stripping or it can be done at block level, which is called block level stripping. this improves speed, but reliability is not increased.\n\na combination of these two, ie., stripping and mirroring comprises a RAID level, which is widely used now a days. \n\nhope this explains about RAID
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Check this out\nhttp://www.networkworld.com/news/2006/011006-ibm-storage.html?nltxstor=0109storagealert2&code=nlstoragealert16241