Did I just F up my build?

[Adaptation]

I'm new, trying to do a build. Bought a bare bone SR2612UR with 12 sas bays. Figured I'd need to add processor, ram and drives.

Get the thing and cant tell how the hot swap backplane connects to the mother board. Pretty sure now that it dosen't. Looks like its got some active mid plane and junk that's muxing it down to just 4 channels... I had read through the Manuel before buying it but I did not understand what I was reading.

If I do get a raid controller will it interoperate with ZFS properly?

Are the backplanes standardized to a level where the tray spacing is identical?
I found this http://www.ebay.com/itm/171034511479 which supports a similar drive configuration, the mounting screws are in a different location but I'm willing to tap new holes in the chassis if I need to.

 

[cyberjock]

Backplanes aren't standardized.. at all. Not necessarily even between a single manufacturer.

And when you mentioned RAID controller and ZFS in the same sentence I threw up in my mouth a little. If you are going to consider that, just delete your data now as that's going to be the end result in the next few weeks anyway.

I'm not sure how much work is entailed with drilling and tapping new mounting screws. But considering the fact that it has to align the sata ports exactly I think this is a very very bad idea and has a very very low chance of success. I mean, your precious data is going to be going through this thing, and as such it has the ability to do really nasty things to your data. Are you sure you want to go customizing that part to make something else fit? I think this is a mistake in the making... even 1mm off can make your SATA ports not align with the hard drives, and then all of it is for nothing.

I tried to look up that rack model number, but I can't find a picture of the normally installed backplane. Can you provide a picture of what you have?

 

[Adaptation]

 

[Adaptation]

Kinda thinking about pulling the backplane completely and just having long enough cables to come all the way out the front, power is a little bit of an issue but it would be even if I swapped out the backplane anyhow. Mostly defeats the purpose for wanting hot swapable bays but it may be the lease bad option.

 

[jgreco]

No, hold on a bit and let me look at this. Wanna figure out what you got but I'm on butt-slow wifi.

 

[Adaptation]

No, hold on a bit and let me look at this. Wanna figure out what you got but I'm on butt-slow wifi.

This may help.

The midplane stuff is on page 32 by print or page 42 by pdf

http://download.intel.com/support/motherboards/server/s5520ur/sb/sr2612ur_tps_13.pdf
http://ark.intel.com/products/41729/Intel-Server-System-SR2612UR

 

[jgreco]

I believe you're all good. If you look at that midplane board, I believe you'll find an SFF-8087 connector on it which is intended to hook up to an HBA or RAID controller. I'm still downloading documents at a snail's pace but my memory suggests this is one of the storage servers that the ServeRAID M1015 was popular in; if one didn't come with your server, you'll want to acquire one, flash it to HBA IT mode, and hook it up with an internal SFF8087 cable and call it a day.

That midplane board should have an LSI SAS expander chip on it which is how 4 channels becomes 12.

Do not fear the SAS stuff - much. It is typically better designed than SATA because businesses expect their servers to Just Work.

 

[jgreco]

Yeah, I was thinking that maybe they had a reverse breakout cable option to the mainboard but it doesn't look like it. I'm pretty sure they require you to take a RAID or HBA controller and use that to attach the storage. You'll end up with a very nice storage server but be sure to read the docs about what's compatible, in particular make sure you pick a CPU with no more than 95W TDP. If you only have one CPU then only certain PCIe slots will be active as well, so again read the docs about where to place any PCIe addon cards.

 

[Adaptation]

I believe you're all good. If you look at that midplane board, I believe you'll find an SFF-8087 connector on it which is intended to hook up to an HBA or RAID controller. I'm still downloading documents at a snail's pace but my memory suggests this is one of the storage servers that the ServeRAID M1015 was popular in; if one didn't come with your server, you'll want to acquire one, flash it to HBA IT mode, and hook it up with an internal SFF8087 cable and call it a day.

That midplane board should have an LSI SAS expander chip on it which is how 4 channels becomes 12.

Do not fear the SAS stuff - much. It is typically better designed than SATA because businesses expect their servers to Just Work.

So when I was looking up the documentation for SFF-8087 it was clear that it was only four channels wide. Wont this reduce my throughput?

So with this raid card I will still get all the smart features?

 

[jgreco]

Your average SATA disk runs about 150MB/sec or 1.2Gbps peak. 1.2 * 12 = 14.4Gbps. 4 x 6Gbps (SFF8087) = 24Gbps. Numbers fit. Additionally you may want to contemplate that your filer will only have 2Gbps of Ethernet connectivity.

 

[jgreco]

and I can't speak to any additional smart features since my downloads are still crawling, except to note that if you use an IBM sanctioned controller everything's likely to work.

 

[Adaptation]

Yeah, I was thinking that maybe they had a reverse breakout cable option to the mainboard but it doesn't look like it. I'm pretty sure they require you to take a RAID or HBA controller and use that to attach the storage. You'll end up with a very nice storage server but be sure to read the docs about what's compatible, in particular make sure you pick a CPU with no more than 95W TDP. If you only have one CPU then only certain PCIe slots will be active as well, so again read the docs about where to place any PCIe addon cards.

I picked a CPU from the compatibly list and it was 95w.

The RAM I purchased was 1600, I was told else ware online that it would still work at 1333 it is RDIMM. 24 gigs, a pack of 3x8 for $100 total, I thought the order would get canceld or something but here it is. Still waiting on the CPU to show up.

 

[jgreco]

Ya no one wants low density RDIMM so its cheap.

 

[Adaptation]

Your average SATA disk runs about 150MB/sec or 1.2Gbps peak. 1.2 * 12 = 14.4Gbps. 4 x 6Gbps (SFF8087) = 24Gbps. Numbers fit. Additionally you may want to contemplate that your filer will only have 2Gbps of Ethernet connectivity.

I am eyeing a 4x gbps addon near term and a 10gbps later.

 

[jgreco]

I am eyeing a 4x gbps addon near term and a 10gbps later.

.... and? So what? It doesn't change anything unless you're planning to do SSD in mass quantity.

 

[Adaptation]

.... and? So what? It doesn't change anything unless you're planning to do SSD in mass quantity.

Pretty sure its SAS 3gbps not 6 so that's 12 and I don't know how well it muxes the drives, if its doing some kind of unbuffered time share there could be a serious performance loss. I'm not going to sweat it, I wanted to make a really fast system but more than anything I need something that works. If getting this raid controller will get me going on ZFS in a safe way with reasonable performance then I'll go with it.

Found documentation for PMC8388, its attached. It is 4 sas chanels at 3gbps.

I've been reading up on sas expanders until my head hurt. It seems like its something standard not something goofy lintel was doing on there own like I ignorantly thought. I was completely unaware of this technology and it creeped me out, now that I understand it a bit more I'm more ok with it. Also if you are accessing three drives in the same arrogation you will be limited to a total of 3gbps not 12. Not a big fan of oversubscription like this if it was 6gbps it wouldn't matter so much, oh well going to have to live with it.

I looked at the M1015 but my expander and backplane only support SAS 3gbps anyhow so I think I would like to get a cheaper one. How do you know which controllers are flashable to HBA IT mode and which ones are compatible with link expanders. Is ram onboard the controller desirable or is that irrelevant in this configuration?