VBR - repository - RAID 6/10 and stripe size?

[JTT]

Hello!
Just for heads up, before going live with a new VBR server/repository - all in a single physical server HP DL380 Gen10 12LFF.
I have HPE Smart Array P816i-a SR Gen10 with 6 x6TB near line SAS- 7,2k drives with four free slots.

What do You all recommend for RAID, i am thinking at least Raid 6 (more usable space, but slower and rebild time?) or Raid10 (less usable space, but faster). Trying also think ahead, RAid10 give almost 6/7tb more free space, than today. But for future, if i need to expand the array, to add more drives - with Raid6 i can expand by one drive, but with R10, two drives.
Also the operating system will be Server 2019 with Refs and 64k block size.
But what should i configure for RAID controller stripe size, 256KB?

[Egor Yakovlev]

HI JTT,
Check Block Sizes section out of this Best Practices page.
Thanks!

[JTT]

Hi

Yes, i have gone over that, but still i little bit confused.
Currently all the backups are configured as "Local target" storage optimization. As i undertand, this should not affect anything?

[Egor Yakovlev]

Well, it all depends on a resultant backup compression rate, and as guide says - its best to test in action prior deployment.
256KB stripe will be 2x more efficient(in terms of IO) than, let's say 128KB stripe, but will have a higher chances of wasting a chunk.

[Gostev]

Average compression is more or less standard for image-level backups (2:1 is a good estimate). Even if some VMs hold highly compressible content, overall it balances out across all VMs.

Currently all the backups are configured as "Local target" storage optimization. As i undertand, this should not affect anything?

Correct. Keep storage optimization setting as is, and follow recommendations in the provided link for your RAID controller stripe size. Thanks!