# Why Is FreeBSD Better Than Linux for Storage Appliances?



## cyberfreaker (Mar 23, 2014)

Hi *e*veryone,

I am a new user to this forum, asking the question here from the gurus who know better as googling doesn't get me any answers to this question*.*

Why is freebsd FreeBSD better than *L*inux or any other Nix apart from the fact that it's stable, as it's being used by top storage vendors such as Netapp OnTap, EMC Isilon, Panasas etc.?


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## wblock@ (Mar 23, 2014)

There's an assumption in the question.  Surely in some situations, Linux is better.

FreeBSD is nice for storage appliances because it has a mature ZFS implementation and the BSD license.


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## cyberfreaker (Mar 23, 2014)

Thank you for the reply, I was assuming because there aren't much Linux based storage appliance vendors who have major market share. Perhaps *I* should have been more clear: is there something special about the storage stack in the kernel optimized for I/O or file services as *I* don't see major vendors use ZFS but their own filesystems . Again *I* want to be clear *I* am not initiating a debate against Linux/Nix  but trying to understand.


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## CurlyTheStooge (Mar 23, 2014)

I work for a known storage/backup and security based firm where their fairly good selling backup appliance uses Linux as base and I believe (not pretty sure) that the filesystem is still ext4. I was discussing with an engineering guy the other day about ZFS/FreeBSD and he didn't have much idea about both.

Regards.


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## ralphbsz (Mar 23, 2014)

In my personal opinion, FreeBSD is better, at least for the "appliance" I run at home.  Reasons: Much more manageable OS (not so much bloat, version changes are under control), not controlled by fundamentally one company (face it, the Linux ecosystem is dominated by RedHat), more stable ZFS implementation.  Actually, I think OpenBSD would be even more suitable, except that it doesn't have ZFS (requiring the use of a separate RAID layer, big management headache), and that it is even further behind on driver support (to the point that using OpenBSD as a wireless AP is virtually impossible, or at least it was when I switched to FreeBSD).

But then, my "appliance" at home is nothing like the style of appliances that Netapp, Isilon, and Panasas sell.  It is neither appliancified (it gets managed by logging in as root and issuing commands, with lots of reading of man pages), nor is it of the scale of these systems.

In reality, the companies you mention don't just "use" FreeBSD.  For example, if you were to take a NetApp, and decide to upgrade FreeBSD to release 10, it would completely stop working.  I don't know exactly which FreeBSD version NetApp's software is based on, but I'm quite sure that it is (a) very old, and (b) considerably modified.  That is one of the advantages of *BSD over Linux: You can modify the source, and ship the resulting system to your customers, without running into GPL hell.  Matter-of-fact, I'm quite sure that one of the major reasons for companies to use *BSD as a base is to avoid GPL hell, and the lawsuits and copyright compliance costs that come with it.

On the other hand, Linux has lots of advantages too.  The biggest two are: (a) Driver support, of the highest quality and the best vendor support, for up-to-date and high-end hardware.  If you call Mellanox or QLogic or LSI or PMC-Sierra and complain about a bug in their device driver in *BSD (or HP-UX or Solaris or AIX or another boutique OS), you may or you may not get help, depending on how much financial clout you have.  If you do the same for Linux, the bug is either already fixed, or they will jump to it.  (b) Stability and performance, in particular for very large systems.  I've seen Linux run on systems that are completely outside the scope of amateurs (and much larger and faster than the building blocks that Isilon or Panasas use), systems whose cost is in the range 10^5 to 10^8 dollars, and with Linux it's usually flawless: Boot from a RHEL or SLES image, and an hour later you have full function and great performance, with little tweaking or tuning required.

The reality is that there are also quite a few vendors that sell storage appliances based on Linux.  Interestingly, there are still vendors selling Windows as a storage server, and they're making good money with that too.

If you are looking for vendors that use ZFS as a storage appliance, there are examples too.  OSNexus comes to mind (they're using ZFS on top of Linux).  There are examples of companies that sell storage appliances based on Linux file systems (although I know of no single example that uses BTRfs, which seems to be considered a data-losing machine, nor ReiserFS, which has serious problems, in particular for the wife).

P.S. (I'm editing this post): Just because I point out some disadvantages of *BSD and advantages of Linux doesn't mean that I'm trying to imply that Linux is the better choice for a storage server or appliance.  Rather on the contrary.  If I were chief architect at one of Isilon, Panasas or NetApp's competitors, I would recommend using FreeBSD as the base operating system.  In reality, engineering is the art of the compromise, and various operating system bases have advantages and disadvantages.  I'm just correcting the rather black and white exaggeration of the original post.


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## ralphbsz (Mar 23, 2014)

cyberfreaker said:
			
		

> I was assuming because there aren't much Linux based storage appliance vendors who have major market share.


According to the most recent IDC numbers, here is the order of market share in external disk:

EMC (which includes Isilon, but that is still a small fraction of all EMC, the bulk is other systems)
NetApp (which includes the former LSI Engenio line, which is not BSD based)
IBM
HP
Dell
Hitachi
others (including Panasas, which is tiny on the scale of these giants)


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## stuckonlinux (Mar 23, 2014)

We have a lot of IBM storage and the SAN Volume Controller, V7000, V5000 (essentially all Storwize products) are Intel-based and use a modified version of Linux.
The V7000 Unified fileservers use RHEL 6.x with IBM GPFS as does their SoNAS products.  If you have a problem, just call IBM and they'll figure out if it's GPFS or Linux.  If Linux, they'll call Red Hat.
The DS8Ks use Power/AIX.
I don't have any XIVs yet so not sure what they're using. 
I like the products.  They're definitely storage appliances though.  You log into very restricted shells(except the Unified fileservers--you can get to root level on those).  The newer stuff has a nice GUI that's run off an internal webserver.
The Oracle/Sun ZS32 storage appliance is Intel/Solaris11/ZFS. 
Pretty sure all our SAN and networking switches are running Linux under the hood.

Naively, I would think it would be difficult for a storage vendor to adopt any of the *BSDs as there are no multi-billion dollar companies supporting them.  I guess NetApp is willing to take on that role and build up the expertise in house.


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