234 reputation
110
bio website blog.norman.cx
location England, United Kingdom
age 43
visits member for 5 years, 6 months
seen Nov 19 at 14:03
C#, Javascript, DHTML, MSSQL developer.

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awarded  Nice Question
Nov
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awarded  Popular Question
May
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awarded  Yearling
Sep
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awarded  Commentator
Sep
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comment Is RAID5 more robust than RAID1
Some interesting stuff, but you've repeated the RAID1 fallacy that I hear all the time. RAID1 does not have to mean that it can only survive a single disk failure. You don't have to have just two disks in your RAID1 array. For example you have a RAID1 array with 3 disks it will survive two disk failures and also read performance should increase (if your RAID system is reading from multiple drives on a read).
Aug
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awarded  Scholar
Aug
17
accepted Is RAID5 more robust than RAID1
Jul
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awarded  Student
Jul
29
comment Is RAID5 more robust than RAID1
That link looks interesting, but does it actually explicitly say anywhere on that page or brochure that they recompute the parity on all reads ?
Jul
29
comment Is RAID5 more robust than RAID1
I'm afraid your answer amounts to "I don't know whether any RAID5 implementations check the parity on a read" and so doesn't answer the question.
Jul
29
comment Is RAID5 more robust than RAID1
I'm afraid you haven't answered the question, which is very precisely about what actual real implementations of RAID5 do with respect to checking the parity data on a read.
Jul
29
comment Is RAID5 more robust than RAID1
I'm afraid this doesn't really answer my question, my question is very precisely about whether or not typical RAID5 implementations check the parity data on read. And for the record RAID1 does not need an even number of disks. You can quite happily have a RAID1 array with more than two disks in, thus increasing redundancy while reducing write speed.
Jul
29
awarded  Critic
Jul
29
comment Is RAID5 more robust than RAID1
I'm well aware of the pro and cons of hardware/software RAID and I'm happy with my choice of software RAID for this implementation. Thanks anyway.
Jul
29
comment Is RAID5 more robust than RAID1
I understand, forget I ever mentioned checksums. I have updated the question to clear up the confusion. The question is all about whether RAID5 systems typically check the parity data on reads.
Jul
29
comment Is RAID5 more robust than RAID1
I disagree with your recommendation of hardware RAID over software in all cases. With modern hardware, software RAID can be just as fast as hardware if your server has plenty of spare CPU (which mine will always have). Also, hardware RAID has some downsides, the main one being in a recovery situation you need a matching RAID card. With software RAID you can pull a drive out of a machine, stick it in another one and away you go without getting a new RAID card that exactly matches the old one.
Jul
29
awarded  Editor
Jul
29
revised Is RAID5 more robust than RAID1
Cleaned up checksum vs parity confusion
Jul
29
comment Is RAID5 more robust than RAID1
He was talking about parity. He was claiming that on RAID5 the parity information was retrieved on a read and compared to the data coming from the other disks to check that there were no read errors.
Jul
29
awarded  Supporter