Trying to decipher IO options of supermicro motherboard (alien.top)

submitted 11 months ago by draetheus@alien.top to c/homelab@selfhosted.forum

1 comments fedilink hide all child comments

I'm currently running TrueNAS Core on a Atom C3558 board for typical desktop NAS purposes: https://www.supermicro.com/en/products/motherboard/a2sdi-4c-hln4f

I'm building out a vmware cluster and trying to figure out if I can simply upgrade my existing NAS with a 10GB NIC and a couple enterprise SSDs to provide shared storage for the cluster. I would not want to use my 4 x 10TB RAID-Z pool as vmware storage since RAID-Z is apparently bad for block storage, plus spinning rust is slow on IOPS.

I'm using the builtin 4 SATA ports, but there is a MiniSAS HD port available for 4 extra SATA ports via breakout cable. I was reading the motherboard manual and unfortunately it seems like there is not enough IO to run the MiniSAS HD port with 4 extra drives AND the PCI-E slot at full bandwidth for the 10GB NIC? I'm not 100% sure since the wording is not clear:

This is a feature on the -2C/4C models only. Up to a total of 8 in selected combinations of SATA ports and four lanes on the PCIe slot can be made available at any given time. Mini SAS offers 4 SATA ports from the Mini SAS HD header. The options are [Mini SAS/SATA (3:0)], [PCIe x2/Mini SAS/SATA (1:0)], [PCIe x4/SATA (3:0)], and [PCIe x4/Mini SAS].

you are viewing a single comment's thread
view the rest of the comments

[-] merkuron@alien.top 1 points 11 months ago

Maybe it’s clear this way:

For every 2 lanes you want allocated to the PCIe slot (up to 4), you lose two SATA lanes. Since there are 8 lanes total, but 12 possible lane destinations, they pre-made combinations of destinations that they think would be useful:

All 8 lanes to SATA, 4 onboard and 4 through MiniSAS
2 lanes to PCIe and 6 to SATA, 2 onboard and 4 through MiniSAS
4 lanes to PCIe and 4 to SATA, either activating the 4 onboard ports or the MiniSAS (but not both)

this post was submitted on 25 Nov 2023

1 points (100.0% liked)

Homelab

371 readers

2 users here now

Rules

Be Civil.
Post about your homelab, discussion of your homelab, questions you may have, or general discussion about transition your skill from the homelab to the workplace.
No memes or potato images.
We love detailed homelab builds, especially network diagrams!
Report any posts that you feel should be brought to our attention.
Please no shitposting or blogspam.
No Referral Linking.
Keep piracy discussion off of this community

founded 1 year ago

MODERATORS

communick@selfhosted.forum

rglullis@communick.news