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Hyper-V on RAID5

Hi All,

Has anyone had experience implementing a small Hyper-V solution on internal 15k SAS drives, configured in RAID5. Do the write overheads cause delay/Degradation in performance to the overall environment. Is the cost per MB worth the jump to RAID 10(or RAID 0+1)? This is for a small solution, and a SAN/Storage array is not on the cards,

I appreciate any feedback,
Thanks in advance!
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We have a number of clients with this configuration and haven't had any issues in the past...May not be as quick as RAID10, but in production it runs great...

Andrew Hancock (VMware vExpert / EE Fellow)VMware and Virtualization Consultant
Fellow 2018
Expert of the Year 2017

RAID 10 is best for read and write performance in an ideal world, it does depend as to your loading, and the VMs you are wanting to use versus RAID 5.

What makes more of a difference is the number of spindles.
kevinhsiehNetwork Engineer

Is your situation such that a RAID 10 array would be too small? If not, then there isn't really a capacity penalty. I am also thinking that a 4 drive RAID 10 using 10K drives will have more available IOPS than a 4 drive RAID 5 array using 15K drives, so you can get larger 10K drives for the same cost. Most of my VMs write 3 or 4 times as much as they read. I think that this is because of the various housekeeping activities that Windows does, and the fact that it can avoid reads by using cache, but every write must go to disk.
Principal Consultant
Large Raid 5 Arrays can take a day or more to rebuild when replacing a failed drive.  big performance hit - causes unneeded worry to customer about their data.  raid 5 rebuilds do fail.  a rebuild completely rewrites all data across the array.

since 2008 all of my builds have been raid 10, faster is better, have never lost an array.