nas raid5

[Data Recovery issues] RAID5 when a hard drive offline, processing degraded state, this time the normal suggestion is to replace the hard disk to do rebuild to restore the complete data status, if there is hot spares, will automatically do rebuild, this is appropriate? Answer A set of RAID volumes will rarely read all of the disk space on the physical hard disk after a long period of time, which is even more impossible. In some cases, the hard driv

0 10 1 11 1 0==============================================The A and B values here represent two bits, where A and B are the same, the XOR result is 0,a and B are different, the XOR result is 1, and knowing the XOR result and any of the values in A and B, you can send out another valueNote: Hot spare or Standby driver: In order to enhance fault-tolerant functionality and to enable the system to rapidly rebuild data in the event of a disk failure to maintain system performance, a typical disk ar

=" Wkiol1z06bdjti9faaeb7eu2ul8823.png "/> A , the result is identified as sda7 as faulty , for damage, while the SDA10 free disk automatically tops and updates the data synchronously650) this.width=650; "src=" Http://s1.51cto.com/wyfs02/M02/78/0D/wKiom1Z06arQT8PfAALMjEtbF9s824.png "title=" 12.png "Style=" Float:none; "alt=" Wkiom1z06arqt8pfaalmjetbf9s824.png "/> - , remove the bad disk:650) this.width=650; "src=" Http://s4.51cto.com/wyfs02/M00/78/0C/wKioL1Z06bjRWypWAABT0x-TpWY394.png "title=" 13

The Linux kernel Adventures of the MD source code interpretation of 14 RAID5 non-bar readReprint Please specify Source: Http://blog.csdn.net/liumangxiongIf it is read in a non-bar, then at least two bars of reading are involved, it is necessary to read the data separately from the two bars, and then the whole result is returned to the upper layer. Next we will see how to split a complete bio read request into multiple sub-requests to the disk, return

Welcome to use ueditor! Let's take a look at the whole scene again: 1 Call the Md_wakeup_thread wake main thread when running the array 2 main thread call Md_check_recovery check Sync3) Md_check_recovery function to check the need to synchronize calls Md_register_thread create a sync thread 4 synchronization thread calls the Md_do_sync function to handle the synchronization process 5 Md_do_sync do synchronization process management, step by step synchronization point, record Sync completion

, smoky car of the manager, I was thinking about the reason. No clue. Back home Google A bit, originally this may be related to the hard disk, that driver 0 is not the hard disk in the BIOS ID number? Is there a problem? The server uses a RAID5 array that has broken a hard drive and can continue to serve. (The server's hardware is compared to the old Powerage 850 's machine) The next morning came to the office early, the Dell after the After-sale tec

[Data recovery failure description] An HP DL380 G4 server that uses the HP Smart Array controller to mount a homemade disk array consisting of a set of 14 146G SCSI hard drives in a group of RAID5. Operating system for Linux, built Nfs+ftp, as the company's internal file server use. Because the room moved, the administrator by the way to clean the machine, to the new room after the line, unable to identify raid, did not initialize. [Data Recovery

Original article: http://www.mysqlops.com/2011/02/22/raid0raid1raid10raid5raid50raid6raid60%E7%9A%84%E5%8A%9F%E8%83%BD%E6%80%BB%E7%BB%93%E7% AE %80%E8%BF%B0.html   1. Features of raid0Data is separated on several disks. Data is divided into many

Solution: Use Orca to configure RAID 5 The f8. Press F8 to enter the array Configuration tool rbsu. Select the first item: create logical drive to go to the array creation page. Use the Space key selection and Tab key

1. raid0 features: data is split on several disks using strip. Data is divided into many data blocks, each of which is written to a different disk. Therefore, the workload of each disk is reduced, which helps accelerate data transmission. Raid-0

Characteristics/advantages 1. Highest read data transaction Rate 2. Medium write data transaction Rate 3. low ratio of ECC (parity) disks to data disks means high efficiency 4. Good aggregate transfer rate Disadvantages 1. disk failure has a medium

In the previous section we talked about the failure of the Raid5_align_endio, which joins the request in the array retry list in the callback function, and after the raid5d thread is awakened, the RAID5D thread calls the request Retry_aligned_read

Baarf Links Why should I not use RAID 5? -art S. Kagel Is RAID 5 really a bargain? -cary Millsap Baarf's opening words Baarf is invented by James Morle on Wednesday the 4th of June, 2003, in the Grange hotel outside A beer or two with Mogens

In terms of overall performance (data security and speed), RAID5 is certainly better; in terms of Data Reading, raid1 is the fastest; in terms of data security, raid1 is the best; in terms of data writing, raid0 is the fastest. RAID5 has both these advantages. Understanding disk array raidI. Functions1 high-speed disk access (acceleration): Raid forms a disk array of General hard disks and writes data to t

Added the connlimit module when rhel5.1/rhel5 does not compile the kernel. System environment and related software packagesOperating System: Red Hat Enterprise Linux Server Release 5 (2.6.18-53. EL5)Kernel source code path:/usr/src/kernels/2.6.18-53. el5-i686Iptables-1.4.0.tar.bz2 # download point: www.netfilter.org -- In fact we only need his source code.Patch-o-matic-ng-20080214.tar.bz2 # download point: www.kernel.org -- Simple Environment[Root @ RAID5