300gb (15,000 RPM) SAS vs.150gb x 2 Raptors RAID-0 (10,000 RPM) SATA

[gramarye]

I suggest you go buy a LSI SAS 8344ELP controller. LSI is a very reputable name in the SAS / SCSI industry. That controller has 128MB of onboard cache and the retail kit comes with cable ( 4 connectors ) that is compatible with both SAS and SATA drives.

There is a few for sale here:
http://search.ebay.com/search/searc...ftrt=1&ftrv=1&saprclo=&saprchi=&fsop=1&fsoo=1

Make sure you ask them if it comes with cables, as some sellers are selling the bare OEM card.

Be careful, the Highpoint RocketRAID 3520 is only a SATA controller. You will not be able to run a SAS drive with that controller.

I'd also recommend an LSI controller. If you need eight internal ports, the 8308ELP would be a better choice than the 8344 as wasserkool suggests.

(in the interest of full disclosure -- I'm biased towards LSI controllers as I'm a member of LSI's SAS controller hardware validation team...)

Are those LSI cards you guys speak of compatible with Mac OS X? Booting EFI-wise?

Also, coincidentally, I shot an e-mail to both ATTO-Tech and HighPoint-Tech with parallel questions, maybe I'll post up the transcript and responses from both. Then again, maybe I shouldn't since there's a disclaimer stating that all these e-mail responses are private.

Looks like the HighPoint RocketRAID 3520 is out of question, though I did some research on it today, it had some incredible benchmarks and reviews! I was sold to this card knowing that fact it came with cables as well.

Anyway, I guess I'll reiterate what I'm looking for, I'll list the requirements:

- Must have (2) SAS internal port
- Must have SAS controlling capabilities [For example: It needs to be able to run a 300GB Seagate Cheetah 15K.5 SAS Drive Primarily]
- Must be able to run 4-SATA Hard Drives [*no RAID necssary, JBOD will suffice]
- PCI-Express of PCI-X [preferably PCIe x8 at least]
- Must have Mac OS X Compatibility


Anything else I should include?

 

[wasserkool]

I did a quick check on LSI's site, it seems that their SAS controllers don't have Mac OS X support ...maybe our SCSI master here can answer that.

 

[gramarye]

I did a quick check on LSI's site, it seems that their SAS controllers don't have Mac OS X support ...maybe our SCSI master here can answer that.

Thanks for looking that up, at least it's less options for me, I was also considering my server workstation to be on windows...but I guess we'll find out. I found some really inexpensive adaptec and dell-OEM ones.

On another note, ATTO-Tech replied with my e-mail and said that that particular card supports the 300gb Seagate Cheetah 15K.5 SAS Drive.


Also, do you guys happen to know what an "ipass connector/cable" is? And, there is a "True" SAS and a "non-TRUE" SAS? I've reading something about this:

The difference between the 'true' SAS connector (dual-port) and the SATA style (single port) is simply one of keying.

You can hack a SATA signal and power connector to attach to the dual-SAS style socket with a pair of sharp clippers, this is less than ideal however. There are also SAS-to-SATA adapter sockets which takes the 14-pin SAS plug (keyed to prevent SATA cables) and converts it to 2 separate SATA type 7-pin connectors.

Keep in mind, a SATA only HBA card _cannot_ drive a SAS disk. There are many SAS HBA cards which have SATA type internal ports under the assumption that users will be buying SATA disks anyway. This appears to be what Apple has done.

^is that kind of like UICompE02 mentioned, a T-Adapter? If I were to use a T-Adapter, would the bandwith be loss since it's converting SAS to SATA? < are these even recommended at all?

 

[UICompE02]

I did a quick check on LSI's site, it seems that their SAS controllers don't have Mac OS X support ...maybe our SCSI master here can answer that.

There is support for EFI and using LSI SAS controllers under Mac OS X. However, this support is provided by Apple, not by LSI. Also, with the exception of some SATA-Only controllers, no MegaRAID adapters are supported. For example, though, if you order an Apple XServe with SAS, you'll find an LSI controller inside.

Also, do you guys happen to know what an "ipass connector/cable" is? And, there is a "True" SAS and a "non-TRUE" SAS?

An iPass connector is the SFF-8088 (for external connections) or SFF-8087 (for internal connections), which is a 4-lane wide-port interface. This may also be known as iSAS or mini-SAS (they're all exactly the same, I'm not sure why they ended up with three names)

The source you quoted is correct, the only difference really between a connector on a SAS drive and a connector on a SATA drive is the extra bit between the power and primary data connection, which includes a secondary SAS port and also acts as a key to prevent someone from simply pluggng a SATA cable in.

If you can physically bypass the "key" there will be absolutely no difference in performance based on which kind of cable you end up using. The T-card, for example, simply splits the signal out into two separate SATA-style connectors. It does nothing to the signaling or protocol of the signal coming out of the drive. It's basically just a bunch of traces on the circuit board, nothing more.

You can take advantage of that fact to come up with all sorts of creative ways to connect your SAS drives. For example, you can use a bunch of SuperMicro 5-in-3 hot-swap SATA chasis with the extra SATA key Dremeled out for testing with SAS drives.

 

[gramarye]

Here are some responses from the Tech Support e-mails I received the other day:

1) Does ATTO-Tech provide cables in the Retail package? If not, do you sell mini-SAS Cables?
No, this product does not come with cables. [However], We do sell SAS cables here: http://www.attostore.com/cablesandacc.html#sas

2) Is Hardware RAID possible? If not, how about software RAID Mac OS X's "Disk Utility"?
The ExpressSAS H308 is not a RAID controller like the R380. It's only a HBA (host bus adapter). You can perform RAID-0 and JBOD via Disk Utility or our ExpressStripe software. Our RAID card (R380) supports RAID levels 0,1,4,5,10,50 with future support of 6 and 60.

3) Can Mac OS X natively boot off this adapter? If not, will there be any updates for this feature in the future?
Currently, no. It's a possibility. We need to come up with an EFI driver first. That's going to take time. (Only SCSI at this time. Sorry for the inconvenience.)

4) Can this natively boot-off for Windows?
Yes

5) Is there memory built-in? If so, how much mb?
There isn't any memory on the HBA(H308), only RAID(R380) has 256mb (and can be upgradeable to 512mb). The HBA doesn't really need any memory, it doesn't store any info.

6) I've read that many of these MiniSAS adapters are not SAS controllers. Does that fact apply to this adapter specifically?
Yes they are not controllers, they mostly convert External 8088 to Internal 8087


7) Is this diagram a possible configuration?

Yes

8) Is this particular adapter compatible with SAS drives, For example, the Seagate Cheetah 15K.5?
Yes


Thanks for your time,
That's what I'm hear for!

I'm confused about Question 8, "they are not controllers, they mostly convert External 8088 to Internal 8087" < yet, they're compatible with SAS Drives?

almost same questions as above

The [RocketRAID 3520] card utilizes Mini-SAS ports, but is not a SAS controller.
It was designed to support SATA/SATAII hard disks.

1) 2 Mini-SAS to SATA cables (1 meter) are included.
2) No - our interface must be used. Disk Utility could be used to configure software arrays between legacy or JBOD disks ...you must create single-disk JBOD arrays if the disks are new (if you need to use them as separate drives).
The OS will not recognize new disks unless they have been configured into arrays.
If they already contain valid partition tables, they will be recognized as "legacy" disks (and will function normally as stand alone drives).
3) Not currently. We are working on a Mac boot solution.
4) Yes, though drivers are required (they can be installed during the OS installation procedure).
5) 256 MB of DDR II
6) See above.

So pretty much, after the mention that this miniSAS controller is not compatible with SAS drives, I decided to take this adapter out of the list. (Though it's an amazing SATA adapter)

this is the kind of area I consult in, my consulting rate is $150/hr with a half hour minimum, payable via credit card or PayPal.

If that is amenable, I'd be happy to assist you.

-m***

That response made me appreciate [H] so much more than I already do a lot. I don't think I'd ever charge someone for the knowledge of one question.


------------------------------------------------------------------------------------------------------------------------

There is support for EFI and using LSI SAS controllers under Mac OS X. However, this support is provided by Apple, not by LSI. Also, with the exception of some SATA-Only controllers, no MegaRAID adapters are supported. For example, though, if you order an Apple XServe with SAS, you'll find an LSI controller inside.


An iPass connector is the SFF-8088 (for external connections) or SFF-8087 (for internal connections), which is a 4-lane wide-port interface. This may also be known as iSAS or mini-SAS (they're all exactly the same, I'm not sure why they ended up with three names)

The source you quoted is correct, the only difference really between a connector on a SAS drive and a connector on a SATA drive is the extra bit between the power and primary data connection, which includes a secondary SAS port and also acts as a key to prevent someone from simply pluggng a SATA cable in.

If you can physically bypass the "key" there will be absolutely no difference in performance based on which kind of cable you end up using. The T-card, for example, simply splits the signal out into two separate SATA-style connectors. It does nothing to the signaling or protocol of the signal coming out of the drive. It's basically just a bunch of traces on the circuit board, nothing more.

You can take advantage of that fact to come up with all sorts of creative ways to connect your SAS drives. For example, you can use a bunch of SuperMicro 5-in-3 hot-swap SATA chasis with the extra SATA key Dremeled out for testing with SAS drives.

Thanks for taking care of that double post UICompE02

~

It'd be nice to be able to obtain one of the LSI Controllers in those XServes. I wonder which controller number it is, I wouldn't be surprised it would the ones readily available for PCs, and Linux,etc..., with just an EFI-mod/hack for Apple specific standards. (I'm probably wrong )

~

As for the iPass, I guess it's not really something I need after all. If I were to pursue my original intentions with a storage controller, I would only need to 2 cables: (1) mini-SAS to SAS cable for my primary drive, and (2) a mini-SAS to 4x SATA cable (for my 4-SATA Drives)

~
If I really want to look at things more simpler, Essentially, I just need some sort of device and mechanism that would allow a SAS drive and 4-SATA Drives to work. < (If the SATA drives can happen, I'll just use my 4-port SATA card, but it'd be a nice feature for me to get rid of it and be able to implement these ideas together.)

1) Do you think I should still follow through with those original plans with the ATTO SAS adapter? And drop the idea of LSI, Adaptec, Dell OEM controllers due to the EFI (though they are certainly more affordable than the Mac ones)

2) Why are mini-SAS to SAS cables so hard to find? The major storage companies don't even make those cables apparently. I've learned that the Mini-SAS controllers are really intended for SATA drives. Any places you recommend in purchasing miniSAS to SAS [Seagate Cheetah drive] cables?

3) With security/reliability/durability(24/7 usage) in mind, Would you recommend the "T-Card" method? It seems a bit sketchy to me for some reason, but that concern is really from my confused understanding. This is the most inexpensive route, and I certainly have plentiful SATA ports on my board and adapter, however, just one more confirmation this would be going at SAS bandwidth performance and speeds?

"T-Card" Method


I apologize for so many questions...I'll try to promise these will be the last and final.
I've considered all your options, and am down to the final decisions on what would best suit my needs. You guys have provided am illustrious amount of information and knowledge, and I can honestly admit I've learned so much from this thread alone!

Thanks again for everything guys, I sincerely appreciate this so much.

 

[UICompE02]

It'd be nice to be able to obtain one of the LSI Controllers in those XServes. I wonder which controller number it is, I wouldn't be surprised it would the ones readily available for PCs, and Linux,etc..., with just an EFI-mod/hack for Apple specific standards. (I'm probably wrong )

The XServe systems use an LSI SAS1068E controller chip (Which is found on a variety of standalone host adapter boards). Which LSI provides an EFI image to anyone for (http://www.lsi.com/storage_home/pro...as/lsisas3442er/index.html?locale=EN&remote=1). You could use an LSI 3442E controller, but there is no support for hardware RAID 5 on those. It is limited to 0, 0+1, 1, and 1E. I'll ask around and see exactly what it takes to get an LSI controller working on an Apple system...

1) Do you think I should still follow through with those original plans with the ATTO SAS adapter? And drop the idea of LSI, Adaptec, Dell OEM controllers due to the EFI (though they are certainly more affordable than the Mac ones)

Unfortunately I don't have any experience with Atto controllers, so it's hard to make a recommendation either way. But if it meets your needs, it may be the route to go.

2) Why are mini-SAS to SAS cables so hard to find? The major storage companies don't even make those cables apparently. I've learned that the Mini-SAS controllers are really intended for SATA drives. Any places you recommend in purchasing miniSAS to SAS [Seagate Cheetah drive] cables?

I think the main reason for this is that SAS drives are mostly intended to be placed in special enclosures that have a backplane with a connector for the drive built in. That is probably by far a more common situation than having a single SAS drive hanging off of a cable. I usually check at http://www.scsi4me.com/ to see if a particular cable type exists.

3) With security/reliability/durability(24/7 usage) in mind, Would you recommend the "T-Card" method? It seems a bit sketchy to me for some reason, but that concern is really from my confused understanding. This is the most inexpensive route, and I certainly have plentiful SATA ports on my board and adapter, however, just one more confirmation this would be going at SAS bandwidth performance and speeds?

I think there may be a little confusion here. Even if you are using a T-card, you will still have to connect the other end to a SAS controller. If you connect to a SATA controller, it won't work.

I apologize for so many questions...

No problems there, that's why we're here! SAS controllers supporting SATA drives is a great feature, but it seems to lead to no end of confusion because of all the various connectors and connection possibilities -- everyone is a bit confused by all of it.

 

[gramarye]

The XServe systems use an LSI SAS1068E controller chip (Which is found on a variety of standalone host adapter boards). Which LSI provides an EFI image to anyone for (http://www.lsi.com/storage_home/pro...as/lsisas3442er/index.html?locale=EN&remote=1). You could use an LSI 3442E controller, but there is no support for hardware RAID 5 on those. It is limited to 0, 0+1, 1, and 1E. I'll ask around and see exactly what it takes to get an LSI controller working on an Apple system...

That sounds great if you can, maybe this could be something manageable, and others in my position could possibly consider. Maybe a slight chance? Anyway, like my above requirements mentioned, RAID is not necessary for my situation, so I guess that no hardware RAID feature is fine. I believe there's always RAID via Disk Utility in Mac OS X, but I don't think I'll bother with that...at least for now. I found a few via: http://www.google.com/products?hl=en&q=LSI+3442E&scoring=p , though many seem out of stock.

And I'd appreciate that a lot if you do ask around about configuring the controller to work with Apple. Another nice feature is native booting, if possible. Thanks!

Unfortunately I don't have any experience with Atto controllers, so it's hard to make a recommendation either way. But if it meets your needs, it may be the route to go.

Currently, that specific ATTO controller is at a pretty decent price, if I could manage to find a miniSAS to SAS [8482] cable, than I guess I have less worries, however, I'm curious to know about the LSI above. But if that requires a lot more work, I must have to just settle for this ATTO.

Whats an interesting fact is that, I don't need miniSAS, it just happens to be this controller uses it. If I could go with a regular SAS controller, that would make things a lot easier as far as finding the right cables (I think SAS cables are cheaper than miniSAS cables as well). If I could find a SAS controller, that'd be a better option, and I believe that the LSI controller you mentioned is regular SAS, which is positive thing.

I think the main reason for this is that SAS drives are mostly intended to be placed in special enclosures that have a backplane with a connector for the drive built in. That is probably by far a more common situation than having a single SAS drive hanging off of a cable. I usually check at http://www.scsi4me.com/ to see if a particular cable type exists.

Thanks for that site, it looks like a great one, and seeing so many gives me more hope about this configuration.

I was wondering, could you recommend me a miniSAS to SAS cable that would work? I can't seem to find one. If there isn't one, I guess we can go with the T-Card method as a backup plan. Though I would prefer not converting, but at least there is something to fall back on.

I think there may be a little confusion here. Even if you are using a T-card, you will still have to connect the other end to a SAS controller. If you connect to a SATA controller, it won't work.

I understand it now, thanks for clarifying that confusion. Basically the T-Card will make the SAS act like a SATA drive with a SATA output, and having this option would allow me to use those MiniSAS to SATA cables that can be found more easily vs. the MiniSAS to SAS cable. But it takes 2 x SATA cables to read the 1 SAS drive?

No problems there, that's why we're here! SAS controllers supporting SATA drives is a great feature, but it seems to lead to no end of confusion because of all the various connectors and connection possibilities -- everyone is a bit confused by all of it.

Thanks and thanks UICompE02. There is certainly a lot of confusion and it is, like you said, endless! But to see things more optimistically, I'm starting to see the other end of the Tunnel, I think we're almost out of there!

 

[gramarye]

Do the power connectors in a SAS Hard Drive utilize the same power connectors as with SATA drives?

And the company I plan to order cables from mention that the SAS drives takes the exact same SATA cables as the SATA drives? Is this correct? I don't want to run into any malfunction problems, this stuff can get expensive.

 

[gramarye]

I found some really inexpensive mini-SAS/ipass to 4x SATA cables for anyone thats interested:

MOLEX &#8212; CABLE ASSEMBLY, IPASS TO SATA
http://www.newark.com/jsp/search/productdetail.jsp?SKU=13M3656

SUPERMICRO IPASS to 4x SATA
http://www.etech4sale.com/SUPER_MICRO_64CM_IPASS_TO_4_SATA/CBL-0188L/partinfo-id-394825.html

- I found that searching "IPASS" had much more results vs searching "mini-SAS" (or other variations of that).

 

[UICompE02]

Do the power connectors in a SAS Hard Drive utilize the same power connectors as with SATA drives?

And the company I plan to order cables from mention that the SAS drives takes the exact same SATA cables as the SATA drives? Is this correct? I don't want to run into any malfunction problems, this stuff can get expensive.

Well, yes and no...

The pinout on the power connector is the same, but you can't just plug in a SATA power connector from your power supply. The reason for this is that the connector on a SAS drive is one long, continuous block that contains the power connector and both SAS ports. So if you try to plug a SATA power connector in, you'll be blocked by the additional piece of plastic that connects the data portion and the power portion which is not present on a SATA drive.

The same holds true of the the SATA data connector. You won't be able to plug in a single SATA data cable because of the extra piece of plastic containing the second SAS port.

See page 12 of this presentation for a picture of what I'm talking about: http://www.scsita.org/aboutscsi/sas/tutorials/SAS_Physical_layer.pdf

 

[gramarye]

Well, yes and no...

The pinout on the power connector is the same, but you can't just plug in a SATA power connector from your power supply. The reason for this is that the connector on a SAS drive is one long, continuous block that contains the power connector and both SAS ports. So if you try to plug a SATA power connector in, you'll be blocked by the additional piece of plastic that connects the data portion and the power portion which is not present on a SATA drive.

The same holds true of the the SATA data connector. You won't be able to plug in a single SATA data cable because of the extra piece of plastic containing the second SAS port.

See page 12 of this presentation for a picture of what I'm talking about: http://www.scsita.org/aboutscsi/sas/tutorials/SAS_Physical_layer.pdf

I can understand the extra piece of gap of plastic from the diagrams, thanks.


Okay, so Seagate Tech Support can't really help me out with confirming the pins on the SAS drive. Can I have the confirmation that a SAS output is a 29-pin?


If so, I'd be looking for a mini-SAS to 29-PIN SAS cable connector. If that cannot be found, I'll go with the T-adapter method. Did not know how complicated cables get. :\

 

[GIGANTOID]

If you factor the time you've spent researching the absolute fastest drive subsystem for what seems to be straight forward graphics use against whatever possible time savings that system may provide its probably a wash.

Just go for the Raptor OS/program drive with the Hitachi storage drive and stop worrying about it and get to work.

 

[gramarye]

If you factor the time you've spent researching the absolute fastest drive subsystem for what seems to be straight forward graphics use against whatever possible time savings that system may provide its probably a wash.

Just go for the Raptor OS/program drive with the Hitachi storage drive and stop worrying about it and get to work.

Thanks Boss! (jokes) No seroiusly...thanks for this, I mean really, you are perfectly right in every way. I came to that realization last week, thats why I finally just dropped the ball on everything and started working on some editing (time is money! It no longer mattered if i paid a couple hundred dollars more or saved a couple hundred). It came down to what was truly more important. I now have the safety of a reliable drive with substantial capacity along with performance.

Everything came in, now I need a cable, and I can finally say I'm done. No worries, my deadlines have kept me busy, and with this whole Media Duplication/Server workstation project, it has been a long time goal, and I finally took the initiative and found less intimidation and more motivation instead.

I'd have to say I would not have made it as far without the help and encouragement from you guys. So thanks for this, and it's such a nice thing that we have such knowledgable individuals around here. Most importantly, the dedication and the taking the time to write and help me out. I sincerely appreciate all you guys. I've learned so much and gained from this thread, I can feel confident with helping other, and sharing my acquire knowledge.

 

[GIGANTOID]

I hope I didnt come acress as speaking down to you.

I truely only read your first post and then was routed to your previous one. And seeing a couple other people looking to get the absolute perfect drive system but spending either an inordinate amount of time or money researching it. A problem I'm WELL aware of having done it myself.

 

[gramarye]

I hope I didnt come acress as speaking down to you.

I truely only read your first post and then was routed to your previous one. And seeing a couple other people looking to get the absolute perfect drive system but spending either an inordinate amount of time or money researching it. A problem I'm WELL aware of having done it myself.

yup, no worries you certainly mean well, and I'm with you on every point. I'm learning, and to be honest with you, after all of this, I can declare that I'm over this, meaning I'm done with the whole computer upgrading/building experience. It's quite an exciting thing to understand the complexities involved in just a simple thing. But the knowledge was worthwhile. Something I have benefited and gained from, and I hope others have as well. Again, thanks.

 

[gramarye]

Just thought I'd report back. All the cables, drives, and controller cards are working fine and everything looks great. I would not have gotten this far without all the help you guys provided. So thanks for all that.

I've gained so much knowledge from this thread, I hope all these questions/answers and readings could help provide the same things I got out of it for others.

~

*Just a quick note: How come this cable was never brought up in this thread?

Single Port Host Based 7-Pin SATA TO Target Based 29-Pin Drive
Receptacle w/ 6" Pwr Lead
http://www.cs-electronics.com/sas-cables.htm

Can be found for sale here:

SAS to SATA with LP4 Power Cable
http://www.buy.com/retail/product.asp?sku=205510527&listingid=13291883&dcaid=17902

1 SATA(Latch Tpye) to SAS 29pin SFF-8482
http://cgi.ebay.com/New-SAS-cable-1...ryZ64459QQssPageNameZWDVWQQrdZ1QQcmdZViewItem


Wouln't this make things a lot easer, and it wouldn't require a SAS Controller as well? (Can be plugged in directly to motherboard). I'm interested, since I'd like to here what you guys know might know or might share about this cable. For example: (1) Would it be safe to run this cable for 24/7 operation as a primary drive? (2) Would there be any loss of speed since it's no longer a SAS output, but SATA?

 

[UICompE02]

(1) Would it be safe to run this cable for 24/7 operation as a primary drive? (2) Would there be any loss of speed since it's no longer a SAS output, but SATA?

I couldn't forsee any issues using this is a primary cable for your drive.

However, you cannot connect a SAS drive to a SATA controller with this cable -- or with any cable for that matter. Well, physically you can, but it's just not possible for a SATA controller to talk to a SAS drive. That functionality is not supported. Although SAS and SATA share some physical-level interfaces, the protocol level is completely different between the two -- but SAS includes SATA within its specification and that's why you can connect a SATA drive to a SAS controller, but not the other way around. However, if you were using this cable to connect a SAS drive to a SAS controller, it will run at the full 3.0gb/s signaling rate and there would be no loss of performance.

 

[gramarye]

I couldn't forsee any issues using this is a primary cable for your drive.

However, you cannot connect a SAS drive to a SATA controller with this cable -- or with any cable for that matter. Well, physically you can, but it's just not possible for a SATA controller to talk to a SAS drive. That functionality is not supported. Although SAS and SATA share some physical-level interfaces, the protocol level is completely different between the two -- but SAS includes SATA within its specification and that's why you can connect a SATA drive to a SAS controller, but not the other way around. However, if you were using this cable to connect a SAS drive to a SAS controller, it will run at the full 3.0gb/s signaling rate and there would be no loss of performance.

Thanks again for the confirmation. I will now close those tabs and take the cables off the list of things I need to get. I guess for now, I'll just figure out how to set my SAS as primary. Once again, I appreciate it, and hope others who are new to SAS may find this thread helpful.

 

[gramarye]

Reporting back, my SAS drive. has been running lovely 24/7. I can bet this thread alone can answer almost any question someone new to SAS drives may have.

Just a side note, this one is a bit complicated, is it okay to combine the remaining SAS/SATA cables with optical drives and other sata hard drives. Like a hybrid mixture. I have this cable: 3ware CBL-SAS8087OCF-06M

I basically have 3 extra SAS/SATA cables not being used, and I'd like to use them on 2 SATA optical drives and a SATA Hard drive.