SuperMicro 4U 24-BAY Chassis - Gotcha's??

[NoProblemAtoll]

Hello everyone. I am new to this forum and this is my first post. I am really glad to have found STH given all the good information and really smart people on here. I am in the process of upgrading and replacing my primary system and I am currently building a new Dual E5-2670 v1 system.

I initially I thought I was going to go with a Norco 4U 24-bay (24x 3.5”) chassis however I am now leaning toward going SuperMicro after finding some really competitively priced Super Micro 4U 24-BAY Chassis options (and even some 4U 36-BAY chassis options). However, while in reading about SAS expanders I noted comments that there may be some hidden nuances with SuperMicro 4U 24-BAY Chassises in regard to the various backplanes models available and their respective compatibility with certain size drives, SAS Expanders, Raid controllers, etc. Can I get some help understanding the SuperMicro 4U 24-BAY Chassis - Gotcha's?? Are there certain backplanes models to avoid? Or are there part numbers to explicitly seek out that are known to have the broadest compatible? Also I need a PCI-E 16x slots so opposed the the Intel and SuperMicro boards that tend to be outfitted with PCI-E 8x slots I am leaning toward using a Asrock Rack EP2C602. Any issue with mounting that motherboard in the in a SuperMicro 4U 24-BAY Chassises? Also any caveats to be aware of with the Super Micro 4U 36-BAY chassis options (36x 3.5” bays)?

 

[nephri]

Hi,

You have few backplanes for CSE846 chassis variants


BPN-SAS-846TQ
It has no expander, you must connect each of theses 24 SAS/SATA ports to HBAs.
So for this you will require more than one HBA (if you use a 8 ports HBA, you will need 3 HBA for connect all drives).
You must use splitter cables like:
- SFF-8087 to sas/sata (4 ports per cable) in order to connect the HBA to the backplane for use with a SAS2 HBA
- SFF-8643 to sas/sata (4 ports per cable) in order to connect the HBA to the backplane for use with a SAS3 HBA

The advantage of this backplane is to support SAS3 HBA, that means it can be an entry level to SAS3 area.
The SAS3 compatibility is not certified from SuperMicro.

BPN-SAS-846A
It's the same than BPN-SAS-846TQ, it has no expander.
But instead to have 24 single SATA/SAS ports to connects, you have 3 SFF-8087 ports.
With this backplane, you will reduce the cabling mess.
In term of capabilities, it's the same. If you use a SFF-8646 to SFF-8087, you could use SAS3 HBA (but it's not certified from SuperMicro)

BPN-SAS-846EL1
It has one expander supporting only SAS1 version.
That means you will may have issues with disk larger than 2 Tb.
With spinning disks, the SAS1 bandwidth maybe not a large issue, but with SSD it's a very bottleneck.
It has only one expender, so you can't use the "dual port" SAS feature that allow a redundency path from HBAs to the disks.
You use SFF-8087 to SFF-8087 cable (just one) for connect the HBA to the backplane

BPN-SAS-846EL2
It's the same than the BPN-SAS-846EL1 except it has 2 expanders that allow the "dual port" SAS feature.
But you have same limitations in term of bandwidth and 2 Tb limit.
For using the dual-port, you need 2 cables and 2 hbas instead of one

BPN-SAS2-846EL1
The most popular backplane for "home labs".
It has one expander, so you haven't "dual port", but this backplane supports SAS2 protocol.
You haven't any issue with disk larger than 2Tb but bandwidth will be a limit with SSD (24x SSD will saturate 4x SAS2 lanes)
You use SFF-8087 to SFF-8087 cable (just one) for connect the HBA to the backplane
It seems, you can connect 2 cables in order to have better bandwidth (8 lanes instead of 4 lanes), but i have no experience with this.

BPN-SAS2-846EL2
It's the same than the BPN-SAS2-846EL1 except it has 2 expanders that allow the "dual port" SAS feature.

BPN-SAS3-846EL1 / BPN-SAS3-846EL2
Variants with the support of the SAS3 protocols.
It requires SFF-8643 cables (instead of SFF-8087)


Don't hesitate to correct me if i'm wrong somewhere.
Séb.

 

[maze]

TQ/non-expander backplanes are a pain (imo) .. the amount of cables are pretty much eliminating the already limited amount of space behind the backplane.

I am personally changing my TQ at the next chance I have.

 

[NoProblemAtoll]

That is all very helpful. All of the low priced SuperMicro 4u 24-bay Chassis's I was looking at have the least desirable BPN-SAS-846EL1 option. Where is the best place to price and buy alternate backplanes?

 

[CyberSkulls]

eBay will probably be your best bet on the backplanes. It will probably be cheaper to buy a chassis with the SAS2 backplane already installed. I myself run multiple 846 chassis with the BPN-SAS-846EL1. My preference is 2TB reds so I never had an issue with the backplanes. For me it came down to price and there was zero advantage or cost savings by going with 8TB reds vs 2TB reds.

I just run mine as media storage so I never cared about a bottleneck as I will never encounter it.

I also have one of my chassis outfitted with (22) 3TB drives. Those older backplanes will typically run drives larger than 2TB as long as the server isn't fully populated aka all 24 bays full.

So for me I chose that route and will begin upgrading to SAS2 backplanes when used SAS3 backplanes start being available in qty of eBay which will drive the price down for the used SAS2 market just like the SAS2 backplanes have done for the pricing on the SAS1 backplanes currently.

Now right now the pricing seems to be high for the SAS2 variant but I have seen them listed as low as $200 for just the backplane. So you just have to watch. Just some food for thought.


Sent from my iPhone using Tapatalk

 

[Hzz]

You mention using a non supermicro mobo with the chassis, be aware you'll need a split cable for the front panel. The cable name is; CBL-0068L.

I got two 846TQ's that's fully loaded, granted a bit of a cable mess, but ones set up, splendid. I use 2x m1015 cards with 1x RES2SV240 expander in each chassis for maximum throughput, very happy with both of them.

 

[Terry Kennedy]

TQ/non-expander backplanes are a pain (imo) .. the amount of cables are pretty much eliminating the already limited amount of space behind the backplane.

I like the non-expander, non-TQ versions of the backplane. But then again, I make all of my cables custom:

This is an SC836, but you get the idea...

The next time I do one of these systems, I'll take a picture of the backplane area with the fans removed - very neat with folded cables (these custom 3M flat cables can be folded into 90° or 180° bends with no loss of signal integrity).

 

[SteveO]

I've got the 900TQ with passthrough SAS backplane and it works just fine. Need to keep in mind you'd need a SAS expander or in my case 3, 8 port HBA's. With this don't have to worry about any drive capacity issues. If fan noise is concern, 1200w PSU PWS-1K21P-1R is significantly quieter than the 900w.

 

[Gene]

I may be getting ready to sell my fully fleshed out sc846 with upgraded sata 2 backplane correct full pullout rails and 702p silent psu (along with the normal 1.1kw ones). Trying to upgrade to the hgst 60 bay 240v next week. Im gonna get rid of it at cost or less so may be a good option if someone wants one

 

[5mall5nail5]

What is the most economical SuperMicro 4U you guys are seeing combined with an expander backplane for > 2TB? Like, what pricing are you seeing? I am likely picking up a Norco 4224 or 4220, which doesn't have an expander, but I am open to suggestions.

 

[Gene]

The sas2 backplane is going for around $200 (i won one in an auction for $125 last year but got lucky). You can get the sc846 sas1 version for about $200 shipped. Someone mentioned you can use sas1 backplane with larger drives if you dont fill it up completely

 

[5mall5nail5]

Yeah I need to hold 18 4TB disks (SATA). Is there a chassis/backplane combo PN# I can hunt on eBay?

 

[Gene]

I searched for supermicro 846. Comes up with multiple sas1 24 bay cases for $200 including shipping. Im not seeing any bpn-sas2-846 sata2 expanders though or 846s with sata2 expander. Pm'ing you. What are you looking to spend as i could be literally about to sell my sas2 846?

 

[CyberSkulls]

I just did a search as well and not many SAS2 models out in the wild right now which is odd.

As Gene mentioned, you can also swap out the backplane very easily if you happen to find a good deal on just the SAS2 backplane. They are generally pretty expensive but occasionally they do pop up for under $200 and sometimes you get that good deal on one like Gene did.


Sent from my iPhone using Tapatalk

 

[maze]

Just swapped my non-SQ psu for an SQ that I bought off @sfbayzfs a few weeks back.

Wauw.. WAF just went to a new level.. really a good investment if you have one of these in an inhouse place

 

[NoProblemAtoll]

I haven't seen much of a selection on ebay the last couple weeks. I had really been hoping to find a chassis with a SAS2-846EL1 or SAS3-846EL1 already installed. Other than the BPN-SAS-846TQ's the only other option I have seen is a lone BPN-SAS-846A . While I'd rather wait and buy what I really want right off, I do need to finish this build so I need to get off the fence and get something going.

It looks like my options would be between:
- $320 for SUPERMICRO 4U 24-BAY 846E1-R900B (2x 900W PSUs) for $200 (shipped) and then drop another $120 to change out the BPN-SAS-846EL1 it comes with for a SUPERMICRO SAS846TQ 4U 24 BAY Backplane.
- $430 for a SUPERMICRO 4U 24-BAY SC846ba-R920 (2x 900W PSUs) with BPN-SAS-846A with rear 2.5" SSD Mount kit, and Rails.

While I could go with the BPN-SAS-846A I have read Backplane has Drive LED Activity indicators that do not quite act right when connected through this backplane. Is that valid? What are the other different variables to take into consideration with the BPN-SAS-846TQ vs the BPN-SAS-846A. TQ has messing cabling which doesn't really bother me unless it impacts airflow and thereby causes heat issues. TQ will also require (3)x 8-Port HBA's opposed to (1)x HBA with the BPN-SAS-846A? What is the cost consideration associated with HBA's? Would it make up for the additional $100 the BPN-SAS-846A system would run me? This is my first build using SAS extenders, SAS HBA's, and considering FreeNAS (ZFS) so I am still developing my understanding of the nuances, hardware involved, and associated costs. (Also I am still leaning towards a traditional hardware controller RAID60. Am I missing out on new advancements?) In the past I have always just used storage directly connected to Dell PERC SAS RAID controllers (max of 8 drives per controller). If I needed more than 8 drives I would use 16-Bay commercially offered entry-level SANs like an EonStor.

While I will be using (24)x Seagate 2TB, SATA 6Gb/s, 64 MB Cache drives initially I do still want to have the ability to migrate to larger drives in the future. (Running out of storage space on a 16-bay 32TB {RAW} SAN is what prompted this new build in the first place). That said, the few times I tried Hitachi or Seagate 3TB drives they seem to fail much sooner/faster than all 1TB and 2TB drives I’ve traditionally used. (Like predicted smart failures and throwing errors that cause my PERC H700's to start rejecting drives from the arrays as failed within 12-36 months). As such, I have since shied away a bit from consumer grade drives and those with capacity larger than 2TBs although maybe my experience spawn from badly chosen drive models or older drive technologies

As far as controller’s go, I have several Perc H700's around. Are those viable controllers to use or should I just buy IBM m1015 cards with RES2SV240 expanders as suggested above?

 

[Gene]

The TQ backplane is fine. Plus it can eventually be upgraded to sas 3 if needed since it is a pass through. I don't see why the perc H700 wouldn't work if you have one already. Datasheet says it can handle 128 drives so 24 is nothing. I think there are ways to flash LSI firmware on it as it is pretty much an LSI 9260-8i that can handle sas 6gb/s
The h700 into an expander like the intel RES2SV240 would give you 5 8087 ports while using one of the 8087 ports on the H700 card. With sas to sata x4 fan out cables that would be 20 sata ports. One more fan out cable into the open port on the H700 would give you the other 4 sata cables you need. If there is a motherboard going in, you could also connect up using the mobo's sata ports for extra devices. If you have ssd's anywhere, you would want to put half on the expander, half on the direct 4 sata ports going in to H700 to maximize bandwidth available to them

 

[pc-tecky]

Oh boy.. I've seen this all before. While it wasn't clear to me then, it is so much clearer now for me. The SuperMicro 846 chassis with SAS1 is noted to be problematic with larger drives (3.0TB+) and 3.0Gbps (old). Using the TQ pass-through back plane is ugly but cheaper and it works with wider range (6Gbps). The most "ideal" used systems I looked had asking prices at $1100-$1800 as a complete solution and others have stated their opinion that they are over priced. YMMV.

I know that eBay seller tamsolutions has 846 (24x 3.5") for under $300 and 216 (24x 2.5") for under $200. (fair prices and local to me.)

I would strongly encourage getting PWS-1K28P-SQ or similar SQ PSUs. You will likely need to dremel the connector ends off the PDB or the PCB of the PSUs. The older PWS-902-1R are rather loud for living quarters and apartment dwellers - vacuum cleaner loud.

The Intel RES2SV240/RES2CV240/RES2CV360 (and dual link to the expander is another option to consider). [FYI: OEM-XS countered at $190 + S&H (from $150) for 360 model] Also see: STH FreeNAS HBAs. Chenbro and [green PCB] HP SAS Expanders are also options to consider.

 

[Rand__]

Oh boy.. I've seen this all before. While it wasn't clear to me then, it is so much clearer now for me. The SuperMicro 846 chassis with SAS1 is noted to be problematic with larger drives (3.0TB+) and 3.0Gbps (old). Using the TQ pass-through back plane is ugly but cheaper and it works with wider range (6Gbps).

Is that limited to 6Gbps or will a TQ support 12Gbps as well if the controller supports it?

 

[Gene]

TQ is a straight direct hardware passthrough so yes any TQ backplane can do 12Gb sas 3 if your sas setup supports it