Opinion On SAS Expander For 24 Drive Build

[Hinatanko]

I have recently finished building my new server for FreeNAS. I have researched how to hook up my drives (24 drives using the norco rpc 4224) via SAS Expander and want to verify if this is the best option before making any purchases:

1 HBA - IBM ServeRAID M1015 (already installed)
1 SAS Expander - Intel SAS Expander RES2SV240 (does this look correct and like a good deal?)
6 cables x 3.3ft Mini-SAS to Mini-SAS cables (is this the correct amount and do these cables look fine? do i need different cables?)

If this is correct? I am not sure if these are the right cables or if i need any more or not.

Would it be better to to buy 2 more HBAs?

If this is correct do I hook up one cable to the hba and the rest to the expander? Do I need the HBA? I thought I did but I could be wrong.

Any information is appreciated!

Thanks!

 

[Ericloewe]

I am not sure if these are the right cables or if i need any more or not.

If you want to connect 24 drives, you'll definitely need more. You're at least one short.

If this is correct?

Depends on the backplane. If you have a sucky one, you might need breakout cables (eww).

Would it be better to to buy 2 more HBAs?

Depends on your cost function.

Do I need the HBA?

Yes, of course.

 

[Hinatanko]

So the backplane I am using has 6 mini-sas connectors. I assume I can use mini sas to mini sas to avoid using breakout cables? I want to keep the amount of cables down to a minimum.

Is the Expander I picked work well with the HBA? I have seen it recommended.

It seems like the cost for 2 more HBAs is similar in price to an expander ($180 for a new expander that I linked above). I can probably find 2 more of the same HBA around $90-$100. If I have 3 cards vs 2 I would imagine that makes it easier for a card to die and cause issues in the future though.

It seems like 1 expander and 1 HBA is the best option but I am mostly just looking for some confirmation before making any purchases.

So for the cable setup would I connect 5 of the ports from the expander to the backplane and then 1 port from the expander to the HBA. And I can use the remaining port on the HBA to go to the backplane to populate all of the backplane ports? If this is correct I would need 7 mini sas to mini sas.

 

[Ericloewe]

. I assume I can use mini sas to mini sas to avoid using breakout cables?

Of course.

Is the Expander I picked work well with the HBA? I have seen it recommended.

Yes.

It seems like the cost for 2 more HBAs is similar in price to an expander ($180 for a new expander that I linked above). I can probably find 2 more of the same HBA around $90-$100. If I have 3 cards vs 2 I would imagine that makes it easier for a card to die and cause issues in the future though.

That's not something I'm concerned with. That kind of concern is in a while different price range.

So for the cable setup would I connect 5 of the ports from the expander to the backplane and then 1 port from the expander to the HBA. And I can use the remaining port on the HBA to go to the backplane to populate all of the backplane ports? If this is correct I would need 7 mini sas to mini sas.

Yes.

It seems like 1 expander and 1 HBA is the best option but I am mostly just looking for some confirmation before making any purchases.

Either way is fine.

 

[Hinatanko]

Okay thank you that answers all my questions!

 

[Scharbag]

The Intel card you chose is a good one. I used that model for years and it is great.

Cheers,

 

[Stux]

You can either connect one port of the HBA to the expander, having thus 6 ports for the Norcos 6 ports. The issue is that you then have 20 drives running through a single mini SAS cable. Oh well.

Alternatively, you connect both ports of the HBA to the expander and now you have only 4 ports. And then you use dual reverse breakout cables from the motherboard to get the last two ports you need.

Alternatively you use a second HBA and the motherboard, instead of an expander.

Alternatively you use a third HBA as well and don't use the motherboard.

 

[Mr_N]

Using 3 HBA's would be rather a waste of PCI-E slots but since you have 5 that's not going to be much of an issue.
I'm always wary of 'good deals' when it comes to electronics on ebay, surely you have plenty of PC shops in the US which could supply it for you?
Amazon is only $25 more :)

 

[Hinatanko]

All of the M1015 I saw on eBay were around $70-$80. I went with eBay because it was recommended on the forums and the seller had a good enough rating. I did buy my first card off of Amazon. Even though it was from Amazon it was from a third party who ships the card in a paper yellow envolpe so I am not sure if Amazon will be much better quality or not.

If any of the HBAs fail is their any risks of data corrupt (or other issues) when replacing them?

 

[Jammin]

I'm considering the same options as you OP and was just wondering what you went with in the end, and if it's working well for you.