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What is "Enable Bitmap" on my Qnap NAS? Will it allow me to recover data in case of failures?

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up vote 3 down vote accepted

"Bitmap" is used to allow faster RAID rebuild times, but you will be able to recover without it if you have a proper RAID level enabled.

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I have RAID 5... So the only thing about it is speed, non increased safety, right? – Pitto Oct 13 '11 at 15:21
Yes, this is correct. The bitmap is said to reduce the speed a litle during normal operation while speeding up recovery. – Sven Oct 13 '11 at 15:22
Do I have a chance to disable it later? – Pitto Oct 21 '11 at 14:38

If I remember correctly, it allows you to recover data faster. (Only in certain RAID scenarios though.) Here's a link -ignore the bickering- that should help.

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Nice link, though in fairness I feel that the bickering is fairly applicable in this case, too. – MadHatter Oct 13 '11 at 15:34
agreed, but not very suitable to helping everyone else get to the answer! – Ben Campbell Oct 13 '11 at 15:38

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