Suggestions on Storage chassis (was Broadcom SAS 9305-24i)

[Forza]

Hi. I'm looking to maybe get the Broadcom SAS 9305-24i HBA adapter together with a Supermicro 24 bay chassi. Is this a wise choice, or should I go with 3x cards that does 8 disks each?

https://www.supermicro.com/en/products/chassis/4U/846/SC846BA-R920B

Host Bus Adapters

Broadcom Host Bus Adapter (HBA) cards can enable an easy, long-term storage growth strategy in practically any direct-attached storage scenario.

www.broadcom.com

 

[NugentS]

Do you have 3 spare PCIe3x8 slots for 3 cards - that the real question here - or do you need the slots for something else?
New / Second Hand?
SSD's or HDD's
So - how long is a piece of string?

 

[jgreco]

Is there a reason you want to do this? It mostly only makes sense for SSD's. For normal HDD's, using an expander backplane (SC846BE1C) chassis with a regular -4i or -8i card would be sufficient. If you are going with SAS disks, maybe the SE846BE2C.

Don't know what I'm talking about? Feel free to mozey on over to

https://www.truenas.com/community/r...o-be-sas-sy-a-primer-on-basic-sas-and-sata.48

 

[Forza]

Do you have 3 spare PCIe3x8 slots for 3 cards - that the real question here - or do you need the slots for something else?
New / Second Hand?
SSD's or HDD's
So - how long is a piece of string?

A new build. And yes I have three pcie x8 slots.

Will be ssds and hdds in various configuration.

 

[Forza]

Is there a reason you want to do this? It mostly only makes sense for SSD's. For normal HDD's, using an expander backplane (SC846BE1C) chassis with a regular -4i or -8i card would be sufficient. If you are going with SAS disks, maybe the SE846BE2C.

Don't know what I'm talking about? Feel free to mozey on over to

https://www.truenas.com/community/r...o-be-sas-sy-a-primer-on-basic-sas-and-sata.48

The reason is simply availability at our reseller. Also supermicro only has some SKUs as globally available. The model I linked is the only global sku we could reasonably find.

The cost difference between the 8i and 24i card is about 300€. But since the only backplane I can find is the one with 6 sas connectors, what can I do?

 

[jgreco]

Well, your basic choices are either actual HBA ports or an SAS expander, whether that is on the backplane itself or a separate expansion card.

If you can afford the PCIe slots, three -8i HBA's will likely be cheaper than a -24i HBA.

 

[NugentS]

and no single point of failure. If you are running SSD Pools then don't get the cheapest LSI cards as they don't necessarily have the IOPS for an SSD Pool (depending up on pool config)

 

[Forza]

Cheapest available to us is an Intel HBA for 300€. The LSI SAS 9300-8i SGL is 350€ and the Broadcom SAS 9305-24i is 650€.

So 3x LSI is more expensive than the one Broadcom. And I leaves me with two spare pcie slots.

There is no way to use a breakout cable from the 8i card to feed the 6 ports on the backplane?

 

[NugentS]

Broadcom almost certainly = LSI Chipset
Oh and remember IT Mode

 

[Forza]

Broadcom almost certainly = LSI Chipset
Oh and remember IT Mode

Yes it is LSI 9305 chipset. It's not a RAID controller, so I assume it would work as is with TrueNAS?

Link to the model: https://www.broadcom.com/products/storage/host-bus-adapters/sas-9305-24i

 

[jgreco]

Yes it is LSI 9305 chipset. It's not a RAID controller, so I assume it would work as is with TrueNAS?

Link to the model: https://www.broadcom.com/products/storage/host-bus-adapters/sas-9305-24i

That 9305-24i may not work "as-is", but it will be flashable to proper firmware for the job, so it's fine.

The way you use a "breakout cable" to make a single SFF8087 on the HBA feed all six SFF8087's on the backplane is to use an SAS expander, as previously pointed out.

Broadcom almost certainly = LSI Chipset

Broadcom bought Avago bought LSI. The underlying chips are all of LSI design.

 

[Forza]

That 9305-24i may not work "as-is", but it will be flashable to proper firmware for the job, so it's fine.

The way you use a "breakout cable" to make a single SFF8087 on the HBA feed all six SFF8087's on the backplane is to use an SAS expander, as previously pointed out.

I believe you need a sas expander to connect a single SFF8087 to multiple SFF8087.

 

[jgreco]

I believe you need a sas expander to connect a single SFF8087 to multiple SFF8087.

Which is why I said:

The way you use a "breakout cable" to make a single SFF8087 on the HBA feed all six SFF8087's on the backplane is to use an SAS expander, as previously pointed out.

 

[Forza]

Which is why I said:

Right. But yea, that's not cheaper I think.

 

[jgreco]

Right. But yea, that's not cheaper I think.

That totally depends on what's available to you. On the used market, the expander backplane and -8i is typically the cheapest option as the resale value of the E1 and E2 chassis is not that far off what the A chassis goes for. The 6Gbps discrete expanders are also pretty cheap. Buying new can be a bit more challenging, as things tend to be stupid-expensive or hard to source. I realize the latter may apply to you. However, these things are definitely cheaply available in the US.

 

[Forza]

uying new can be a bit more challenging, as things tend to be stupid-expensive or hard to source.

You are very right here! Since I am buying for the company, I can only buy from specific vendors too =(.

Thanks for all the feedback and help! Based on what's available I think the 24 channel Broadcom/LSI SAS non-raid card is the best choice.

One last thing. The SAS card has 6x SFF-8643 and the backplane has 6x SFF-8087, but I assume a suitable cable should work?

 

[NugentS]

Cables are available at a wide range of prices - a very wide range

 

[jgreco]

One last thing. The SAS card has 6x SFF-8643 and the backplane has 6x SFF-8087, but I assume a suitable cable should work?

Yes, but... 12Gbps SAS has been pretty standard for some years now. Supermicro didn't stop selling the 6Gbps chassis, but the only global SKU right now is the 12Gbps chassis with SAS expander built in.

https://www.supermicro.com/en/products/chassis?pro=filter=formfactor&formfactor=4U&mlg=?mlg=0

shows the 846BA as a non-global SKU, and if you drill down, you'll see that's because it stopped being a recommended solution after the X9 and X10 boards came out. The only current global SKU 24-bay 4U chassis is this one with the SAS expander.

https://www.supermicro.com/en/products/chassis/4U/846/SC846BE1C-R1K23B

I am just saying be careful. You can totally get the cables to make this work out,

 

[Forza]

You're right about the global SKU. I wonder why they (the vendor) lists it.

So a better fit might then be:
MB: SuperMicro X11SCL-F
CPU: Xeon E-2126G
Chassis: SC846 BE1C-R1K28B - backplane has 2 ports I think. Costs 500€ more than the SC846 BA-R920B!
Controller:
option 1: LSI SAS 9300-8i SGL. 8 channels. 2 ports - (350€)
option 2: MegaRAID SAS 9341-4i. 4 channels - 1 port (270€)
option 3: Adaptec RAID 8405E. 4 channels - 1 port (250€)
option 4: LSI SAS 9305-24i. 24 channels - 6 ports (650€)

 

[jgreco]

Just commenting on the chassis situation, I think the BE1C would be my choice (notice I mentioned it in post #3) along with the 9300-8i. This is mostly because it seems like it'd be somewhat more futureproof, and easier to wire up too.

I don't really have anything AGAINST the 846BA plus 9305-24i solution. It'd work, and if it's cheaper, okay. For a SATA pool, it'll be fine. For a SAS pool, it will probably work fine even at 12Gbps, but it was designed for 6, and that just doesn't feel quite right coupled with the 12Gbps HBA. Just OCD on my part, probably.