LSI9211-8i question & NAS configurations


New Member
Nov 28, 2019
Good evening Networking gurus :D

I'm after advice before the Cyber Monday sales disappear and the lovely savings on HDD's!

Currently have 2 NAS devices at home and making decision on new drives to add -

1. Synology 1812+ 8 bay (3TB x6 RAID5 + 2TBx3 JBOD) -> backs up my main NAS weekly. 1GBe link

2. Xpenology Home Brew NAS: 6x 4TB RAID6 on LSI 9211-8i HBA; -10GBase-T link to my work PC only

-Looking to expand to 8x 4TB on HBA (and in future have separate physical & logical volume on MB SATA ports)
I use 10GBe link to access NAS like DAS or SAN (sorry for butchering nomenclature :rolleyes:). all other gear accesses it at 1GBe including backup NAS (DS1812).

I need some help Please :)

1. PCIe 2.0 (x8?) LSI 9211-8i - correct specs?
Does each drive channel (SAS channel?) have enough bandwidth to fully utilise a SATA 3 HDD, and will the

PCIe 2.0 : 3,200MB/s max @ 500MB/s per lane (correct?) should be ample.

2. DS1812+ :
I consider buying 3x 4TB and have mixed drives in a SHR2 arrangement that I will grow with 4TB+ drives as I need.

I've read commentary from flawed "studies" that SHR is slow compared to RAID... never used it myself.

I don't use encryption so my Atom CPU should be ok for SHR? ... any hands on experience with SHR2 and its speed VS RAID6?

DS1812 only has 1GBe so unless the SHR array is totally bogged down I'm assuming it will exceed NIC throughput? (no teaming since I only use it for backup from my main NAS, and it cant be fitted with a 10GBe NIC. I know rebuild, scrub times etc are super important too... but they can also happen slow time in background given its core usage pattern.

Appreciative of any input folks may have :).