<p class="shortdesc"></p> <p class="p">Redundant Array of Independent Disks (RAID) is a technology that combines multiple independent disks (physical disks) to form a disk unit (logical unit) in different ways to improve storage performance and provide data backup. Different RAID levels represent different storage performance, data security, and storage costs. </p> <table class="table" id="Introduction__table_bjy_jp4_tlb"><caption></caption><colgroup><col><col><col><col><col><col></colgroup><thead class="thead"> <tr class="row"> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__1">RAID Level </th> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__2">Description</th> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__3">Read/Write Performance </th> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__4">Security</th> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__5">Disk Usage </th> <th class="entry" id="Introduction__table_bjy_jp4_tlb__entry__6">Disks Required </th> </tr> </thead><tbody class="tbody"> <tr class="row"> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__1 "> <p class="p">RAID0</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__2 "> <p class="p">RAID0 stores continuous data on multiple disks to improve storage and access performance. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__3 "> <p class="p"><strong class="ph b">Highest </strong></p> <p class="p">Read performance: N* single disk read performance. </p> <p class="p">Write performance: N* single disk write performance. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__4 "> <p class="p"><strong class="ph b">Worst </strong></p> <p class="p">No redundancy capability. If one disk is damaged, the entire data is unavailable.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__5 "> <p class="p">100% utilization rate of total disk capacity</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__6 "> <p class="p">A minimum of 2</p> </td> </tr> <tr class="row"> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__1 "> <p class="p">RAID1</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__2 "> <p class="p">RAID1 implements data redundancy based on data mirroring, and two disks are used for mirroring to provide data backup. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__3 "> <p class="p">Read performance: It is the same as a single disk and depends on the disk with faster read speeds. </p> <p class="p">Write performance: Data need to be written into two disks in parallel. Therefore, the single disk has relatively slower write speeds. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__4 "> <p class="p"><strong class="ph b">Highest</strong></p> <p class="p">Each disk provides redundancy. Therefore, even if one of the mirrored disks is damaged, data is still available. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__5 "> <p class="p">50% of disk capacity The cost is relatively high. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__6 "> <p class="p">2 or 2N</p> </td> </tr> <tr class="row"> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__1 "> <p class="p">RAID5</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__2 "> <p class="p">RAID5 stores data and corresponding parity information on the disks. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__3 "> <p class="p">Similar to RAID0. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__4 "> <p class="p">Only one disk is allowed to be damaged. </p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__5 "> <p class="p">(N-1) /N of disk capacity</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__6 "> <p class="p">3 or 3N (N≥ 2) </p> </td> </tr> <tr class="row"> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__1 "> <p class="p">RAID01</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__2 "> <p class="p">RAID01 combines RAID0 and RAID1, in which half disks are first grouped into RAID0 stripes and then used together with the other half to set up a RAID1 array.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__3 "> <p class="p">Read performance: Same as RAID0. </p> <p class="p">Write performance: Same as RAID1.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__4 "> <p class="p">The security performance is lower than that of RAID10.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__5 "> <p class="p">50% of disk capacity</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__6 "> <p class="p">4 or 2N (N≥ 2) </p> </td> </tr> <tr class="row"> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__1 "> <p class="p">RAID10</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__2 "> <p class="p">RAID10 combines RAID1 and RAID0, in which two disks are first set up as a RAID1 mirror and then used together to create RAID0 stripes.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__3 "> <p class="p">Read performance: Same as RAID0.</p> <p class="p">Write performance: Same as RAID1.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__4 "> <p class="p">The security performance is the same as that of RAID1.</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__5 "> <p class="p">50% of disk capacity</p> </td> <td class="entry" headers="Introduction__table_bjy_jp4_tlb__entry__6 "> <p class="p">4 or 2N (N≥ 2)</p> </td> </tr> </tbody></table>