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Jump to navigationJump to searchremove additional raid info, it's not specific to sme just google
# the final line becomes ext2online -C0 /dev/md2 (or whatever / is mounted to)
# the final line becomes ext2online -C0 /dev/md2 (or whatever / is mounted to)
====Raid Notes====
====Raid Notes====
Many on board hardware raid cards are in fact software RAID. Turn it off as cheap "fakeraid" cards aren't good. You will get better performance and reliability with Linux Software RAID (http://linux-ata.org/faq-sata-raid.html). Linux software RAID is fast and robust.
Many on board hardware raid cards are in fact software RAID. Turn it off as cheap "fakeraid" cards aren't good. You will get better performance and reliability with Linux Software RAID (http://linux-ata.org/faq-sata-raid.html). Linux software RAID is fast and robust.
If your persisent on getting a hardware raid, buy a well supported raid card which has a proper RAID BIOS. This hides the disks and presents a single disk to Linux (http://linuxmafia.com/faq/Hardware/sata.html). Please check that it is supported by the kernel and has some form of management. Also avoid anything which requires a driver. Try googling for the exact model of RAID controller before buying it. Please note that you won't get a real hardware raid controller cheap.
If your persistent on getting a hardware raid, buy a well supported raid card which has a proper RAID BIOS. This hides the disks and presents a single disk to Linux (http://linuxmafia.com/faq/Hardware/sata.html). Please check that it is supported by the kernel and has some form of management. Also avoid anything which requires a driver. Try googling for the exact model of RAID controller before buying it. Please note that you won't get a real hardware raid controller cheap.
It rarely happens, but sometimes when a device has finished rebuilding,
It rarely happens, but sometimes when a device has finished rebuilding,
====Resynchronising a Failed RAID====
====Resynchronising a Failed RAID====
See http://www.linuxmanpages.com/man8/mdadm.8.php#lbAP
Sometimes a partition will be taken offline automatically. This will happen if, for example, a read or write error is detected in a disk in the RAID set, or a disk does not respond fast enough, causing a timeout. When this happens, the details of the raid can be seen by inspecting the mdstat file. In the following example, partition hda2 (hard disk 'a', partition 2) is offline:
Sometimes a partition will be taken offline automatically. This will happen if, for example, a read or write error is detected in a disk in the RAID set, or a disk does not respond fast enough, causing a timeout. When this happens, the details of the raid can be seen by inspecting the mdstat file. In the following example, partition hda2 (hard disk 'a', partition 2) is offline:
