{{parent page="Storage"}}

===Linux RAID===

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# Scan existing raid config
mdadm --detail --scan
# Scan existing raid volumes and perform assembly
mdadm -A --scan
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Create a volume with missing drive
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mdadm --create /dev/md3 --level=1 --raid-devices=2 /dev/sdb6 missing
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Add a device to a raid volume
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mdadm /dev/md3 --add /dev/sda6
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===Stripe cache===
If you are running raid4,5,6, setting a higher stripe cache may boost write performance signficantly
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echo 8192 > /sys/block/md2/md/stripe_cache_size
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http://linux.derkeiler.com/Mailing-Lists/Kernel/2008-06/msg03344.html