SSD vs 15k SAS in entry level server

Yes this question has been asked a million times but I am going to ask it again. Everything depends on what the server is doing and running and everyone is different. I am looking for a "generic" answer. It is going to be an entry level server. Windows 2012 something. No SQL or intensive database. Just a general purpose server for 20-25 users. I am going to run a Raid 5. That being said which would be better, SSD or 15k SAS?

As kind of a side question I have heard that longevity is a problem with MLC SSD drives. Is that true?
LVL 15
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Scott CSenior EngineerCommented:
As it's an entry level server with that number of users, I'd go with the 15k SAS drives.  

I don't think that one should even worry about SSD lifespan unless they are in a very work intensive environment, where they definitely wouldn't be using a consumer SSD. SSDs have been around since 2007 and, even today, very little is known about SSD end life in typical scenarios because it takes them so long to reach that.

You have to weigh the cost vs. performance.  I'd say in this case I'd side with the cost from the information in your question.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
LockDown32OwnerAuthor Commented:
The whole reason the question came up again was because of cost. A 480GB Intel SSD (Pro 2500) is down to $210. A Seagate Cheetah 450GB 15k SAS drive is $205. The is no price difference. Cost can be removed from the equation. I should have included that above.
You can't just use any SSD in a server. They have to be models that actually work with the RAID controller of the server and which are built for servers. Those will most likely be far more expensive than the models you have looked at (provided the RAID controller even supports SSD's). Besides that I very strongly advise not to use RAID 5. RAID 5 is something that may have been OK a decade ago, when the disks were very small and you had to get the most capacity out of a limited number of small disks but still have some redundancy. But today you have large capacities, and the disks are cheap. There is no need to maximize the capacity and risk your data using a weak form of RAID where a lot can fail. Something like RAID 6 is much better and gives you better redundancy, or also a couple of RAID 1 arrays is safer than RAID 5.
The 7 Worst Nightmares of a Sysadmin

Fear not! To defend your business’ IT systems we’re going to shine a light on the seven most sinister terrors that haunt sysadmins. That way you can be sure there’s nothing in your stack waiting to go bump in the night.

LockDown32OwnerAuthor Commented:
Thanks Rindi. Your comment about not being able to use any SSD in a server is server 101. Not only do you need to get a SSD that is supported by the Raid controller but you need to get a Raid controller that is supported by the motherboard. Hence the server compatibility list.

"Larger capacities and the disk are cheap" really applies more to the SAS and SATA and not so much the SSD drives. You reach a point with the SSD drives where the bang for the buck disappears. I have never had a Raid 5 do anything but run. Even rebuilding was simple but is might be because I use Adaptec. What put such a foul taste in your mouth about Raid 5?
Bill BachPresident and Btrieve GuruCommented:
Weighing in as well:  For an "entry level server", if cost is not a factor (or if the differences are minimal, then I would definitely recommend SSDs where possible.  The system will boot faster, it'll usually respond faster, and it will use less power and generate less heat and noise.  

I do a LOT of work on database servers, and I am not convinced that SSD is right for that environment yet, but any entry-level server will be mostly reading from the drive to serve up files and applications, and writes will be minimal.  Longevity isn't really a factor, then, either, because of the limited writes.

Performance MIGHT be an issue, though.  Remember that the SAS controllers and drives are substantially faster than SATA, especially when running multiple drives in a RAID array.  In fact, your SAS config in RAID5 may outperform a SATA SSD, even.  For an entry-level server, this may not matter, anyway, but it is another factor to consider.
andyalderSaggar maker's framemakerCommented:
Can you get away with 2 drives mirrored instead of 3 in RAID 5? If so ditch the RAID controller and use Windows software mirroring. (Unfortunately Windows software RAID5 isn't bootable so that would need a mirror plus 3 more in RAID5 to implement in software although the boot disks can be low capacity as no data on them)
LockDown32OwnerAuthor Commented:
This whole thing has gotten kind of interesting. All the articles I have read say that it isn't necessarily that Raid 5 is bad it is that there might be better alternatives like Raid 10 or Raid 6. This is all predicated on larger drives being so cheap. Well... about the only larger drives that are truly cheaper are the SATA 6Gb/s. A TB WD RE is $134 at Newegg and that is cheap but they don't perform nearly as well as SAS 15k or SSD and both of those drives are still at a premium to where Raid 5 would actually make sense. Is the only objection to Raid 5 the unhandled read error (or what ever they call it)?

   Not too many entry level servers need TB after TB of storage but what they could use is performance....
Bill BachPresident and Btrieve GuruCommented:
Personally, I see no issues with RAID5.  It provides a good price/performance mix, and you get redundancy from any one failed drive.  RAID10 is definitely faster, and is what I recommend for my write-intensive database customers, but overkill for a "entry-level" system.  RAID6 provides dual redundancy, but can be slower still.  

I would definitely think about avoiding any RAID array implemented in software -- stick with hardware RAID for performance reasons.  Of course, this adds to the price, and takes us back around to the "entry-level" designation.

If it were me, I would look at the following:
1) CPU clock speed: This is still king when it comes to speed.  You won't need lots of cores, so go with fewer cores and faster clock speed if possible.  Think 3.4GHz or faster.
2) Memory: Memory is second for performance.  More RAM allows for more caching, which cuts down on the disk reads needed -- thus improving performance.  Memory is also pretty cheap right now, so think 32GB or more.
3) Disk: Disk usually comes third, because when memory runs out, you have to go to disk.  Again, hardware RAID and fast drives are important, but less so if you've properly done 1 & 2 the right way.
4) All other features:  Redundant power supplies can be important in case a UPS fails.  (Yes, I have had UPS units fail, and YES, my servers with redundant power supplies have survived this failure.  I also had my desktop UPS fail last week, and that computer went down hard.)  Disk size is important, but you can easily migrate data to a NAS and save a LOT of costs.  Power utilization is also important for small facilities -- will they need a dedicated circuit?  A new UPS?  A dedicated cooling system?  These operational costs can also add up.  Also pay attention to the noise profile.  I once purchased a network security appliance for my small office -- but the fans ran at such a high speed and such a  loud whine that I was NEVER able to use it.  It was in the rack for about a year before I took it out & sold it on EBay -- losing money on the deal.  So, don't ignore the noise factor, especially for a small office.

Now, look at the servers within your budget, and start making trade offs.  Save money where you can, and spend it where you want.  Having too much of a budget is a good thing sometimes, but it can lead to buying a box which is a LOT bigger and more costly to run.
I would recommend RAID 1 for the OS and RAID 6 for the data drive, RAID 10 if possible.
I have used RAID 5 for years and have never had a problem, but go with the better technology, RAID 6/10.
Along the same lines go with SSD Enterprise level.
In 4-5 years you won't be looking for a replacement drive as SAS drives start to become obsolete and the next generation of SSD is out.
andyalderSaggar maker's framemakerCommented:
Only objection of RAID 5 in a low write situation like this is the chance of it fasiling to rebuild completely due to bad blocks on a surviving disk plus the write hole which is a risk on any controller that  doesn't have battery backed write cache.
Gerald ConnollyCommented:
The reason RAID-5 is now not recommended with todays v large disks is due to the elevated risk of a second disk failing during the extended rebuild time of a previous failed disk.

Yes, RAID-5 has served us well over the years, but rebuild times with 1TB and above disks, have increased to an unacceptable level.
That was certainly a concern with spinning disks, but I've wondered if that is still the case with SSDs (I haven't had to research the issue yet).  Wouldn't the rebuild take a shorter amount of time, even if you had large SSDs?  (and most people that have SSDs don't have large ones)
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Server Hardware

From novice to tech pro — start learning today.