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19 votes
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SAS / SATA max number of connected disks vs performance

SATA/SAS are not like hubs, rather they work much like a network switch. This means that a single SATA/SAS port provides the entire advertised bandwidth, independently from the other ports. In other ...
shodanshok's user avatar
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11 votes
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How can I connect a SAS drive to USB?

Such device finally exist CXRT SAS to USB adapter CXRT-USB3. You can find it on Amazon, eBay and couple other places. There are 2 downsides in my opinion. It’s almost 100 times more expensive than ...
V0JT4's user avatar
  • 126
11 votes
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HP ProLiant DL380 G7 LFF - Is every SAS HDD compatible?

HPE HDDs will have custom firmware so "ordinary" HDDs even from OE HDD vendor will work just fine (and you'll even keep your warranty, please see my link below) but you won't have special features ...
BaronSamedi1958's user avatar
11 votes
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Can we upgrade Dell's basic Server R240 (which still uses HDD 7200RPM) to an SSD?

On Dell's R210, R220 and T130 I've successfully used Sandisk's consumer grade SSDs for years. I've done this with PERC's H410 and H710 controllers. It will be a matter of controller and controller's ...
Marco's user avatar
  • 1,709
9 votes

Can we upgrade Dell's basic Server R240 (which still uses HDD 7200RPM) to an SSD?

Yes, you can swap HDDs <-> SSDs the way you want. Moreover, it's OK to use non-Dell branded SSDs inside Dell servers, you won't receive support (of course!) and some functions won't work like LEDs, ...
BaronSamedi1958's user avatar
9 votes

NFS SATA vs SAS for VMware datastore?

You missed two things: 15k (and partly 10k) drives were almost killed by entreprise SATA SSD; HDD IOPs are strongly limited by random access, rather than interface bandwidth. Modern high perf ...
shodanshok's user avatar
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8 votes
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3Gbps SSDs in RAID1 VS 6Gbps SAS Drives in RAID1 - Performance Difference?

In most scenarios, including common virtualization workloads, the SSDs will outperform the HDD drives due to lower latency and higher IOPS. The link speed is a lot less relevant than latency or IOPS ...
Bernhard's user avatar
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8 votes

Difference between hard drives

Yes, that is correct. There are multiple reasons for this: SAS drives are sold less, leading to scale effects. They are actually more reliable These 1.2 GB 2.5" are 10k RPM drives, so they are ...
Sven's user avatar
  • 99.5k
7 votes

Performance Difference SAS vs. SATA?

This is a late answer, but I would like to add my opinion. From a pure speed standpoint, a nearline drive (as the ones OP considered) will performs practically the same both using the SATA interface ...
shodanshok's user avatar
  • 50.4k
7 votes
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How much PCI-E bandwidth can my SAS HDD array make use of?

Ah, did you ever bother to get away from the theoretical numbers? You state so nicely... 18 x SAS3 maximum at peak: (1.2 x 18) = 21.6 GB/sec Yeah. Now show me a single hard disc (and you talk about ...
TomTom's user avatar
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6 votes
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3ware 9650se not recognizing SAS drives, what else should I check?

Unfortunately, 9650se is SATA controller and therefore it doesn't support SAS drives.
GioMac's user avatar
  • 4,624
6 votes

How can I connect a SAS drive to USB?

While we can all appreciate the occasional advice on backup strategies and their importance, there are things that even Tivoli won't help you with, so to answer the actual question, in short: To ...
Roy's user avatar
  • 4,446
6 votes
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How to connect two Dell storage arrays to a to a Dell Poweredge server (daisy chain vs direct)?

You can stack the MD unit that way; (In the image its 3 MD, but you can see how) For your openmanage question, yes, it can be used remotly, but be sure to set the routing correctly in the management ...
yagmoth555's user avatar
  • 17.1k
5 votes
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LSI 9211-8i won't boot in KVM

In case anybody stumbles upon this: the solution to such a problem is to set rombar=0 in the PCI passthrough in your vm.conf: hostpci0: 06:00.0,rombar=0 (whereas 06:00.0 is the relevant slot you want ...
Johann's user avatar
  • 66
5 votes
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Accidental SAS cable removal

TL;DR: If you accidentally removed a SAS cable from your server then install storcli and run storecli /call show note the correct controller and enclosure and the nrun #!/bin/bash # Use your ...
Zeta's user avatar
  • 265
5 votes
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what is the difference between a sas controller and a sas raid controller?

A SAS controller (HBA, Host Bus Adapter) on its own has no RAID ability. It just presents however many disks are plugged in to the underlying operating system, and it's the OS's job to figure out what ...
Mark Henderson's user avatar
5 votes
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SAS RAID5 Disk failure, replacement enclosure not matching

You can use the old enclosure and put new disk in to that enclosure, i had done same for my Dell R620 Ensure you not misplace any screws and fit all screws
Vijay Muddu's user avatar
5 votes

SAS RAID5 Disk failure, replacement enclosure not matching

These are the two different drive tray/carrier/sled designs. The Gen8+ Smart Carrier is on the left. The G7 style is on the right. You can swap the bare drive into the Gen8 carrier and be fine.
ewwhite's user avatar
  • 198k
5 votes

How to use 12 HDDs with the Supermicro BPN-SAS3-826EL1 backplane?

If you have the -EL1 backplane, you should be able to see all 12 drives, even with a single cable from the RAID card to the expander backplane. If you don't, something's wrong with the backplane or ...
Arvind Sankar's user avatar
5 votes

SAS Drive Upgrade

Do backup of the whole RAID1 volume. Replace drives and create a new RAID1 Restore backup to "new" RAID1 volume
batistuta09's user avatar
  • 9,096
4 votes

Use of 2.5" Laptop Drives in a Server?

Apparently everyone saying to use enterprise drives...just because...are mistaken. There are several articles from companies that have actually done this vs just making stuff up. In short: ...
user342213's user avatar
4 votes

Anyone seen a meaningful SAS vs SATA comparison/benchmark?

So much misinformation here! I can't imagine a meaningful benchmark between SAS and SATA and I wouldn't bother looking for one. This is like benchmarking a six passenger minivan versus high-speed ...
KD Mann's user avatar
  • 41
4 votes

hp proliant not recognizing emc sas drives

Having worked with HP servers since G2 days I just thought I'd throw my two pence worth in. I have done a lot of unusual things with HP servers for Dev and training purposes. A HP SAS crontroller (...
Luke's user avatar
  • 41
4 votes

ZFS best practices with hardware RAID

Everybody tells that ZFS on top of RAID is a bad idea without even providing a link. But the developers of ZFS - Sun Microsystems even recommend to run ZFS on top of HW RAID as well as on ZFS mirrored ...
Alek_A's user avatar
  • 337
4 votes
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Poor performance with Linux software raid-10

Edit: Your dd oflag=direct observations might be due to power management issues. Use PowerTOP to see if your CPU's C-states are switched too often above C1 under write load. If they are, try tweaking ...
the-wabbit's user avatar
4 votes

HP ProLiant DL380 G5 - Use without Raid Controller?

The RAID controller in an HP DL380 G5 is on an HP Smart Array P400 or E200 RAID controller in a low-profile PCIe slot. You should look for the two SAS SFF-8484 connectors on the system board. Those ...
ewwhite's user avatar
  • 198k
4 votes
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SAS 3.0 cabling without a backplane - SFF-8680 vs SFF-8482

From my comment: SFF-8482 and SFF-8680 are essentially the same connector (fitting to a drive's back), the former SAS2-compliant, the latter also SAS3-compliant. With HDDs, this won't matter in ...
Zac67's user avatar
  • 11.5k
4 votes

Are there any advantages to connecting SATA3 drives to SAS ports?

There's no point really. If you want to get SAS functionality there's a compromise in a way of NL-SAS: SATA drives with SAS interface.
BaronSamedi1958's user avatar
4 votes

Difference between hard drives

Creating IT infrastructure is a huge responsibility and their is ALOT to hardware purchases and investments. If you are not sure about what to get, get in touch with a trusted vendor that can help you ...
Cristian Matthias Ambæk's user avatar
4 votes
Accepted

SAN: FC vs SAS vs iSCSI

"SAN" is a term for a network used to provide access to (block) storage. It can be anything. SCSI is a family of storage protocols that all share a common core but have more or less subtle ...
Zac67's user avatar
  • 11.5k

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