Used hardware recommendation request

[ryanjk333]

Hi,

I've been reading so much about FreeNAS and ZFS over the past year, maybe longer. I'm looking to build my first NAS using used hardware, but also understand that this entire project is not worth doing if I don't do it correctly right off the bat.

I'm hoping someone could comment on the server at the eBay link below. The seller informed me that it comes with ECC RAM and my understanding is that I'll want to buy an M1015 to replace the included Adaptec 5805. Other than this, am I missing anything? My intent is to find a decent used server with about 24 bays and about 24GBs of memory. I'll be filling it with mostly 2, 3, and 4TB drives that I already own, so I need to be sure it'll support the 4TB drives, which the seller said even the included Adaptec card (that I guess I won't be using) would support. And it might be nice to know that whatever I build is likely to support the 5 and 6TB drives that are already out and about.

If anyone has any other links to used, well-priced servers, that would meet these requirements, I'd really appreciate this, as I'm afraid I'm going to overlook something since I'm building my own NAS for the first time.

I should mention that this server will not be doing any transcoding of video - just storing large amounts of HD video, music, and photos in my home.

Thanks so much!

http://www.ebay.com/itm/17212283583...1&exe=13926&ext=35632&sojTags=exe=exe,ext=ext

 

[Mirfster]

May want to see what the resident SuperMicro guys say.

Perhaps they can clarify if:

1. The Chassis Backplane can support >2TB drives (unsure since I just saw that is supports 3Gb and not 6Gb..)
2. How many Mini-Sas Connectors it needs, if more than two you will need additional HBA(s)

Specs Links
Chassis: http://www.supermicro.com/products/chassis/4U/846/SC846E1-R900.cfm
MB: http://www.supermicro.com/products/motherboard/QPI/5500/X8DT6-F.cfm?SAS=N&IPMI=Y

 

[danb35]

Yep, @Mirfster has identified the only real issue with this machine--it uses a SAS1 backplane, which means it's limited to 2 TB drives. That will probably make it unsuitable for you, but if you're sure you won't want to use disks larger than that it otherwise looks good. You'd want to replace the RAID card with an IBM M1015 crossflashed to IT mode, or an LSI 9211-8i. It's a SAS expander backplane, so you'll only need the one HBA.

You probably want the E16 variant of the SC846 instead, which has a SAS2 backplane and supports any drive size in use today.

 

[SweetAndLow]

Also note that I have this case and store it in the crawl space under my house and when the fans are at 50% you can hear it.

Other than that the 846E16 is a great choice.

Sent from my XT1096 using Tapatalk

 

[ryanjk333]

Thanks so much for such quick help!

You probably want the E16 variant of the SC846 instead, which has a SAS2 backplane and supports any drive size in use today.

This helps me a lot...I definitely will have to go with the E16. All these Supermicro options get confusing pretty quickly for a newbie.

I think I need to go back and brush up on my storage knowledge somehow. Any good, free, online resources you're aware of? I'm a bit confused on how all the hard drives are connected to the server. So the drives will connect to the backplane, the backplane connects to the LSI or M1015 card, and then this card is what's connected to the motherboard? What's the difference between a "SAS expander backplane" and an "HBA"?

Based on what you've said, it looks like this server would better suit my needs for 4TB and up drives?

http://www.ebay.com/itm/SUPERMICRO-...989343?hash=item2eec8a689f:g:yqcAAOSwr7ZW3eOR

 

[Valdhor]

I'm a little confused by this. I was under the impression it was the HBA and not the backplane that determined drive support. If the included Adaptec 5805 card supports 4TB drives, what would preclude the use of 4TB drives with an m1015 card?

 

[danb35]

That link looks like it would be a good choice. You'll again want to replace the RAID controller with an HBA as I mentioned above. @jgreco has a sticky in this subforum about SAS stuff that would be helpful in understanding SAS terminology. In short, a single SAS cable from the HBA (host bus adapter--the controller card) to your backplane will handle all your drives.

You may end up wanting to expand the RAM, but I expect that could be done later if needed--24 GB shouldn't be close to max capacity for that board.

 

[ryanjk333]

Also note that I have this case and store it in the crawl space under my house and when the fans are at 50% you can hear it.

I worried about the noise level, too, so I really appreciate your input on that. I'm in a medium-sized 2 bedroom apartment (no basement) and on second floor where it get's warm easily. :( I'd probably put it in the spare bedroom, but that's located pretty much in the center of the apartment. Too loud for a location like that? Sound proofing is tough because of the need for cool temps and good airflow...

 

[SweetAndLow]

Everyone has different tolerances but you will hear it in that room even with fans on low. To keep drives cool you can't use low unless you have ac so you will need about 50% like me.

Sent from my XT1096 using Tapatalk

 

[jgreco]

I worried about the noise level, too, so I really appreciate your input on that. I'm in a medium-sized 2 bedroom apartment (no basement) and on second floor where it get's warm easily. :( I'd probably put it in the spare bedroom, but that's located pretty much in the center of the apartment. Too loud for a location like that? Sound proofing is tough because of the need for cool temps and good airflow...

You're from Wisconsin, just put it outside!

 

[Mirfster]

I'm a little confused by this. I was under the impression it was the HBA and not the backplane that determined drive support. If the included Adaptec 5805 card supports 4TB drives, what would preclude the use of 4TB drives with an m1015 card?

Well, if the backplane where the drives are attached can't support >2TB; how would you suppose the HBA that is accessing the drives via the backplane is supposed to know they are > 2TB? ;)

 

[jgreco]

Well, if the backplane where the drives are attached can't support >2TB; how would you suppose the HBA that is accessing the drives via the backplane is supposed to know they are > 2TB? ;)

I would think that the drive inquiry command that fetches information about the configuration of the drive is the answer to your question. A SAS/SATA drive reports its size back to the host using that mechanism. The problem with LSI 3Gbps is that the logical block addressing stuff in the silicon cannot go past 32 bits of addressing. So it's very possible for a disk to report back that it's a 4TB HDD, but when you try to go and actually order the HBA to retrieve block number 2^32, it instead retrieves block 0, or fails in some other nonpretty way. That's why that condition is trapped as an error in the driver these days.

It hasn't been conclusively demonstrated to me one way or another whether the LSI 3Gbps expanders actually have the 2^32 issue, but I'd suggest just avoiding them. If one of them comes into the shop and I have an opportunity to test, I probably will.

 

[Valdhor]

Well, if the backplane where the drives are attached can't support >2TB; how would you suppose the HBA that is accessing the drives via the backplane is supposed to know they are > 2TB? ;)

My research shows that the backplanes basically pass through the data signals from the HBA. The backplane does not care whether the drive is 2TB or 86500TB. The signals are passed through the cable. Are you saying that the backplane has a microprocessor as well that intercepts requests and processes them? Why would you want to do that? It just slows down data requests from the drive(s). It just seems like a stupid thing to do to introduce bottlenecks in a system.

 

[jgreco]

For a passthru backplane, that's correct, but for a backplane with an SAS expander, which is the majority of them, the SAS expander is definitely in the data path.

 

[Valdhor]

So I have one coming in. I'll try it out and see whether the 2^32 problem exists with it. Due to arrive March 15.

 

[Mirfster]

Well here are some other threads that tend to echo similar concerns:
SAS 1 Backplane Question
Supermicro Build - Using most of the hardware

As well, per SuperMicro's "Summary of HDD tested with SAS2/SAS3 Expanders"; they stated:

SAS1 backplane is going to be obsolete. SAS1 backplane is not able to support SATA 6Gbps (SATA3) or SAS2 hard drives. Please upgrade to SAS2 backplane.

So, even if >2TB was supported, then you may still be limited to SATA 3Gbps.

I do not claim to be a expert with SuperMicro; just wanted to provide info regarding a potential issues for the OP since they mentioned:

And it might be nice to know that whatever I build is likely to support the 5 and 6TB drives that are already out and about.

Should drag @tvsjr in for his advice. As far as I know he has had personal dealings with SuperMicro SAS1 backplanes.

 

[Valdhor]

Yes, That's what I read. Even with SATA 3Gbps you're looking at 175GBps which is more than what a hard disk can run at (Which is at most 150GBps). Unless you're using SSD that shouldn't be a problem.

In that summary document PDF if you look at page 2 they show tested drives in the A/TQ chassis. I checked and some of those are 8TB drives.

There does not appear to be anything concrete on this issue. It's all speculation.

 

[Mirfster]

Found this which may provide more info:

http://www.supermicro.com/support/faqs/faq.cfm?faq=20896

Question
I have a SC846E1-R900B with a BPN-SAS-846EL1 backplane, and I'm wondering if I can use the AOC-SAS2LP-MV8 with it to get access to drives larger than 2TB?

Answer
AOC-SAS2LP-MV8 does not support expanders.

 

[jgreco]

Yes, That's what I read. Even with SATA 3Gbps you're looking at 175GBps which is more than what a hard disk can run at (Which is at most 150GBps). Unless you're using SSD that shouldn't be a problem.

In that summary document PDF if you look at page 2 they show tested drives in the A/TQ chassis. I checked and some of those are 8TB drives.

There does not appear to be anything concrete on this issue. It's all speculation.

No, we *KNOW* that A and TQ 3Gbps backplanes will work. They've just got copper traces on a PCB connecting one socket to another. However, most of the time what's used is an expander backplane. That's where the question is. People buying a 24 bay chassis don't usually get the A or TQ because then you have to come up with 24 ports of HBA or SATA connectivity.