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175

This is going to be a function of your workload and the class of drive you purchase... In my server deployments, I have not had a properly-spec'd SSD fail. That's across many different types of drives, applications and workloads. Remember, not all SSDs are the same!! So what does "properly-spec'd" mean? If your question is about SSD use in enterprise ...


59

Every laptop at my work has either a SSDs or Hybrid since 2009. My SSD experience in summary: What I'll call "1st Generation" drives, sold around 2009 mostly: In the first year about 1/4 died, almost all from Syndrome of Sudden Death (SSD - It's funny, laugh). This was very noticeable to end users, and annoying, but the drastic speed difference made this ...


39

A few items to help clarify SAS technology... SATA drives can connect to SAS ports. SAS drives cannot connect to SATA ports. Server-class hardware typically uses an embedded RAID controller or a separate RAID controller PCIe device. Most RAID controllers and SAS HBAs will use SAS connections (multilane or 4-lane SAS ports). Internally, these systems will ...


21

Reevaluate where you're quoting these items and see what the realistic purchase prices are. I often deploy the HP StorageWorks D2700 and D2600 enclosures and populate them with HP-specific drives. I pay less than $1,000 US for each base unit (without disks). The real cost is in the disk drives. These are usually available in bundles with the enclosure ...


18

SAS is active. It is a Network. a 24 drive enclosure likely has 3 backplanes, each driving 8 drives, chained, and everyone of the them is ACTIVE. It has a full SAS Management chip. As such, it has a CPU, it has some RAM, it has Firmware on every of those backplanes. SuperMicro sells a 5.25" to 2.25" enclosure (put it into two 5.25" Slots) and it costs ...


18

In my experience, the real problem are the dying controllers, not the flash memory itself. I've installed around 10 Samsung SSDs (830, 840 [not pro]) and none of them has made any problems so far. The total opposite are drives with Sandforce controllers, i had several problems with OCZ agility drives, especially freezes in irregular time intervals, where the ...


18

The idea with ZFS is to let it known as much as possible how the disks are behaving. Then, from worst to better: Hardware raid (ZFS has absolutely no clue about the real hardware), JBOD mode (The issue being more about any potential expander: less bandwidth), HBA mode being the ideal (ZFS knows everything about the disks) As ZFS is quite paranoid about ...


16

Your SAS to SATA adapter isn't a protocol translator, just a pin to pin adapter. It won't let the USB to SATA adapter speak to the SAS drive in any language other than SATA... which it won't support. So you won't see anything happen.


15

It's a case of math. I/O-per-second is determined by the following calculation: Random I/O = 1000/ (average latency + seek time) For a 7.2K RPM drive, a seek-time of 8.5ms and latency of 4.16 gives an IOPS number of 78. For a 15K RPM drive, a seek-time of 2.6ms and latency of 2.0ms gives an IOPS number of 217 . For a 15K RPM drive, a seek-time of 3.4ms ...


15

Q. 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? A. It is strongly preferable to run ZFS straight to disk, and not make use of any form of RAID in between. Whether or not a system that effectively requires you make use of the RAID card precludes the use of ...


13

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 words, a chipset providing 4x SATA 3.0 ports (6 Gb/s each) has a "SATA backplane" switching capability of 4x6 Gb/s = 24 Gb/s. For a 4x SAS 3.0 ports (12 Gb/s ...


12

Based on your problem description your issue isn't so much the server as the storage. You want a reliable, robust filesystem like ZFS that's designed to handle large storage capacity well, and has built-in management capabilities to make that end of the system easier to manage. As was mentioned in the comments, I'd go with ZFS for the storage pool (probably ...


11

Most DELL servers, including their latest-generation R/T series, will run non-DELL drives just fine. There are a few exceptions, like the PowerVault MD3000, MD3000i, MD3200, MD3220 and some of their Blade servers. They absolutely require "certified" DELL drives with DELL firmware (no, you can NOT "flash" non-DELL drives with DELL firmware), or they will not ...


11

First, stop and think about your realistic goals... The short answer to your question is that SAS is a switching protocol. The drives connected via expanders are all accessible and can be addressed transparently by a single controller. However, the rest of your questions are going to be a function of your particular controller, your storage architecture ...


11

www.hardware.fr one of the biggest French hardware news site is partner with www.ldlc.com one of the biggest French online reseller. They have access to their return stats and have been publishing failure rate reports (mother boards, power supplies, RAM, graphics cards, HDD, SSD, ...) twice a year since 2009. These are "early death" stats, 6 months to 1 ...


11

Yes, the extensive command set of the SCSI is a big bonus of using it over SATA. from SAS' Wiki: SATA uses a command set that is based on the parallel ATA command set and then extended beyond that set to include features like native command queuing, hot-plugging, and TRIM. SAS uses the SCSI command set, which includes a wider range of features like error ...


11

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 firmware more than server brand/model. Also, you'll probably have issues to find disk trays. I ended up buying it used on a famous refurbished hardware shop. ...


10

Upgrading the HP SAS expander is possible using Linux and a SAS HBA. Note: Flashing firmware to a SAS expander will likely not work when the expander is connected to a SAS RAID controller because that controller might hide all devices behind it from the OS. An example of a SAS HBA is Supermicro SAS2LP-MV8. In case you haven't got Linux, you can use a Linux ...


10

This is how SAS expanders work. You're technically oversubscribed, but in reality, you shouldn't be. Your WD2003FYYS disks link at 3.0Gbps, but are only capable of 1.2Gbps/disk. Your Supermicro drive backplane/expander has 16 ports with 6.0Gbps downlinks to the drives, but a single SFF-8087 uplink to the controller. From what I can tell, this backplane ...


10

You need a SAS expander and/or a server with a disk backplane that has an embedded expander... Please see: RAID card w/1x mini-SAS connector : how do I physically connect 16 disks? and How exactly does a SAS SFF-8087 breakout cable work? + RAID/connection questions


10

It depends on how the drive failed. 72GB 10k disks haven't been manufactured for years, so I'd suspect that your disks are at least 6 years old... possibly 9 years... You may have a mechanical problem with the disk. The server you're talking about is an HP ProLiant DL360 G5. They were sold from 2005-2008. Running RAID 0 is a calculated risk. Your data was ...


10

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 like health monitoring / LED indication working. https://support.hpe.com/hpsc/doc/public/display?docId=emr_na-lpn11980 Question: Will adding third-party memory ...


9

I run ZFS on top of HP ProLiant Smart Array RAID configurations fairly often. Why? Because I like ZFS for data partitions, not boot partitions. Because Linux and ZFS boot probably isn't foolproof enough for me right now. Because HP RAID controllers don't allow RAW device passthrough. Configuring multiple RAID 0 volumes is not the same as RAW disks. ...


9

Cost, capacity and reliability are factors for why SSD adoption hasn't occurred at all levels. SSDs cost more than SAS disks for a given capacity. But in general, servers don't actually come with a particular type of disk. Storage is something that is configured afterwards. Some background information: Are SSD drives as reliable as mechanical drives (2013)?...


9

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, iDRAC etc, but in general it's a way to go.


9

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 server are generally build around SATA + NVMe, unless SAS multipathing is required (ie: a JBOD connected via SAS to multiple head nodes).


8

A few items... You obviously will not be able to address all of them with your existing P410 controller, but: *Do you need all 16 drives in one array?* I ask, because there isn't much utility in having that many disks in a single array unless you know your read/write patterns and are designing around it. If you don't need all 16 disks in a single array, ...


8

Realistically speaking, you're doing your employer a disservice trying to drag a machine with such old technology into the future. It's time to buy a new machine. By the time you spend the time cobbling together this bespoke solution you'll have spent more of their money than just buying a new machine. You're also leaving a major headache for the next person ...


8

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 in most real world workloads, so I guess the difference is not too big. If you want actual numbers, you'll have to perform a benchmark with your workloads as ...


8

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 faster They have specific vendor firmware with proprietary features. You pay a premium for that alone. Also, depending on the vendor, you must use their ...


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