Serial Attached SCSI (SAS) is a computer bus used to move data to and from computer storage devices such as hard drives and tape drives. SAS depends on a point-to-point serial protocol that replaces the parallel SCSI bus technology that first appeared in the mid 1980s in data centers and workstations, and it uses the standard SCSI command set.
Questions tagged [sas]
502 questions
163
votes
5 answers
Are SSD drives as reliable as mechanical drives (2013)?
SSD drives have been around for several years now. But the issue of reliability still comes up.
I guess this is a follow up from this question posted 4 years ago, and last updated in 2011. It's now 2013, has much changed? I guess I'm looking for…
hookenz
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How can a single disk in a hardware SATA RAID-10 array bring the entire array to a screeching halt?
Prelude:
I'm a code-monkey that's increasingly taken on SysAdmin duties for my small company. My code is our product, and increasingly we provide the same app as SaaS.
About 18 months ago I moved our servers from a premium hosting centric vendor to…
Stu Thompson
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47
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What are the merits of SAS vs SATA drives?
What are the merits of buying SAS drives over SATA drives, or vice versa?
username
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ZFS best practices with hardware RAID
If one happens to have some server-grade hardware at ones disposal, is it ever advisable to run ZFS on top of a hardware-based RAID1 or some such? Should one turn off the hardware-based RAID, and run ZFS on a mirror or a raidz zpool instead?
With…
cnst
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Why are enterprise SAS disk enclosures seemingly so expensive?
I will begin by stating that I do not believe this is a duplicate of Why is Enterprise Storage so expensive?.
My question is specifically about SAS drive enclosures, and justifying their expense.
Examples of the types of enclosures I'm referring to…
Sam Elstob
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How exactly does a SAS SFF-8087 breakout cable work? + RAID/connection questions
Please let me know if my question does not makes any sense as I am not sure if I am interpreting it correctly from my thoughts due to my lack of technical knowledge on this.
If I am using a motherboard which has a connection for a SFF-8087 to 4x…
Damainman
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23
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How can I connect a SAS drive to USB?
I have a Dell T710 with Seagate Cheetah 15k.7 SAS disks. If the T710 motherboard dies, I'll need to resort to one of my nightly off-site backups and salvage the journal/logfile from the SAS disk to bring the backup bang up-to-date.
I need a way…
dave
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Sanity check on 40TB server configuration
I've got 40 years in computing, but I've never had to build a server quite like this one, so this might be a n00b question.
I have a client that is going to offer ultra-high def music files for download. In this case that means FLAC-compressed…
Peter Rowell
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Performance Difference SAS vs. SATA?
Can not find that anywhere it seems.
What is the expected performance difference in a storage backend scenario that is heavily parallellized in access (like a SAN, Virtualization host storage etc.) between SAS and SATA, all other things being…
TomTom
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SAS vs Near-line SAS vs SATA
I'm unsure about the differences in these storage interfaces. My Dell servers all have SAS RAID controllers in them and they seem to be cross-compatible to an extent.
The Ultra-320 SCSI RAID controllers in my old servers were simple enough: One type…
Dai
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Anyone seen a meaningful SAS vs SATA comparison/benchmark?
I hear lots about SATA being slower than SAS but I've only found 1 decent benchmark.
http://blog.whitesites.com/SAS-RAID-0-VS-SCSI-RAID-0-VS-SATA-Benchmarks__633689244191943184_blog.htm
In this, SAS comes out on top until you read that the SAS…
boatcoder
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SAS vs. Nearline/MDL SAS - What is the difference?
As subject I guess, looking at SAN's and most vendors offer 10k or 15k "proper" SAS drives, many also offer 7.2k MDL/Nearline SAS drives.
Does anyone have an authoritative explanation of the difference please?
flooble
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So you really can push a SATA2 disk into a SAS backplane?
There's only one SAS, right? Serial attached SCSI?
The female connectors:
SATA2 looks like: ------------| |-------
And SAS looks : ------------+-+-------
For me, the SATA2 male connector looks like it has little corners in the middle that would…
isync
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Any experience with SATA SAS Interposer Cards?
Driven by the current price difference between SATA and SAS disks on one side and the potentially bad behaviour of SATA disks in bigger storage arrays on the other side, I have found so-called SATA-to-SAS interposer cards.
Advertised as "seamlessly…
korkman
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SCSI vs SATA? Is SCSI "actually" better?
Well, I was talking with a guy about servers the other day. I was a bit shocked whenever I asked him if there was any significant difference between SCSI and SATA and why he always uses SCSI. (note, I'm not sure if by SCSI he meant SAS)
He told me…
Earlz
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