Help me come up with best Mac based server and backup solution for a small business.
December 2, 2009 12:27 PM   Subscribe

Help me come up with best Mac based server and backup solution for a small business.


I have been considering either an XServe or new Mac Pro to replace our aging XServe G4. Either way, I would like to have 8TB (4 x 2TB drives) on-site and 8TB off-site storage. Preferably this storage would be rack-mountable, hot swappable, and eSata. Also, hardware RAID is not really important to me and seems to add a lot of extra costs.

I am currently using SuperDuper for backup since it is a) very fast, and b) retains all permissions and ACLs, which is very important to me. I would like to continue using SuperDuper as my backup software.

The XServe's internal hard drives have to be Apple Drive Modules, which are limited to 1Tb each but have many benefits. See:

Due to the space limitations of the internal XServe hard drives, I am considering using an external rack-mount solution for both the on-site drives as well as the off-site ones.

If I go with a Mac Pro, I would be able to use the internal drive bays for the 8TB of onsite storage, and then only need 4 bays of external rack-mountable hard drive bays.

What are my best bets: XServe with 8 bays external storage or Mac Pro with 4 bays external storage? For the external storage, is it standard practice to purchase "server grade" hard drives for backup purposes?

What brand of eSata card is best for this purpose?

What is the best rack-mountable hot-swappable eSata storage solution?

Last but not least, are there any alternatives to all of the above that I may be overlooking?

Thanks in advance!
posted by jesseendahl to Technology (12 answers total) 5 users marked this as a favorite
Best answer: Re. SATA cards: You can use PCI-Express SAS cards. One SAS port can handle 4 to 8 SATA drives. These are usually more compact and cost-effective than pure SATA cards. SAS cards very often have external ports. As one SAS umbilical cable carries the data stream from multiple drives and is much better designed, all layout and reliability is much better with a SAS umbilical. The cost should be the same, approximately - if the first SAS cards you see are over $300, keep looking. You should be able to get a card for $100-200.

Re. alternatives, it depends. If the only thing you want is good technical compatibility with a Mac network + low cost, I'd recommend having a look at a generic x86 OpenSolaris or Nexenta box, running ZFS over commodity hard drives.

If you want the nice OS X GUI management stuff, then you still do want the Mac OS X head, BUT you might still be able to save quite a bit of money by using a cheaper Mac as the Mac-OS "face" of the server solution, while using a ZFS box for the storage backend.
posted by krilli at 1:25 PM on December 2, 2009

One more thought: If storage space and storage speed is the only reason you're considering retiring the XServe G4, you could actually keep it and build a ZFS storage tank under it. You should be able to build a very very soldid ZFS box w. a great number of hotswappable drives for under $1500 (excluding the drives).
posted by krilli at 1:38 PM on December 2, 2009

Xserves are all Intel now, krilli. Apple doesn't make any G4 or G5 (PPC) computers anymore. The Apple store recommends a few different external storage rigs, too.
posted by rokusan at 1:42 PM on December 2, 2009

Sorry! Under $1100, not $1500. Under $1000 is realistic.
posted by krilli at 1:43 PM on December 2, 2009

rokusan - OP has an XServe G4 that I indicated he could avoid retiring, is it possible you misread something I wrote?
posted by krilli at 1:44 PM on December 2, 2009

I did misunderstand, krilli. Apologies all around.
posted by rokusan at 1:55 PM on December 2, 2009

Response by poster: Thanks for the help everyone! krilli—the primary reason for the new XServe is for Snow Leopard / future Intel only releases. With that said, I think I am leaning towards a Mac Pro so that I can use non-proprietary drives. Not only does it get me non-proprietary drives, and up to 2TB per drive instead of 1, it would also get me four internal bays (Mac Pro) instead of three (XServe).

Thanks for the info about the SAS cards. Running one cable is definitely more convenient than four. Any specific links for a good card?

Regarding the actual housing/box for the storage.... would something like three of these be a good idea?

I have read up a bit on ZFS before, so I understand the benefits there, but I am a little foggy on what you mean by "ZFS storage tank" and "ZFS box." Do you mean building a separate computer that has lots of bays, and then sharing the files out directly from that machine over the network? Or do you mean something like what I linked to above? I should mention that everything does need to be shared over AFP or NFS since I am using Portable Home Directories.

Thanks again for all your help everyone.
posted by jesseendahl at 7:30 PM on December 2, 2009

Best answer: Promise are AFAIK Apple's chief storage-expansion vendor. They sell SAS and SATA cards, as well as rackmount boxes that are simply containers for hotswappable drives.

At the very least That Elitestor box looks the part! Physically, as well as description-wise. I don't have any concrete experience with it myself.

OK if you aren't familiar with ZFS already, then IMO the ZFS thing is probably not worth it for you. What matters most is that you get the backup system running, and are comfortable with it and that it is a good tool for you. You might "save" some money if you look only at the hardware, but if we factor in the time you'd need to take to familiarize yourself with ZFS and Mac OS X interoperability ... you would come out at a loss in this context.

But for the record, when I say "ZFS box", I'm thinking about a special-purpose computer built with generic commodity hardware. It runs Solaris of some kind and has several hard disks, all redundantly pooled into a giant ZFS "drive". This computer can be a server itself, running servery tasks like databases and stuff, OR it can present itself exactly like any other hard drive to another server, using iSCSI over Ethernet for instance.

Logically, it's exactly like buying a Drobo and hooking it up with Firewire to a Mac Pro. The Mac Pro just sees a big old disk and wants you to use it for Time Machine and everyone is a happy little triumvirate. What's happening differently behind the scenes is that gives you a lot of flexibility, fault-tolerance and multiple levels of data integrity.

It's really cool, BUT it does take some learning and administration. So I think it's not the best way for you.

Talk-out-of-ass: I would think and guess that the XServe might be more expensive for what you want it to do - part of the cost of the XServe is fitting all the goodness into a tight space, needed if you want to put lots of them in a datacenter. So if the XServe seems more expensive w.r.t. capability, that would be my guess as to the reason. So I think the Mac Pro idea is absolutely not bad.
posted by krilli at 2:52 AM on December 3, 2009

Best answer: Thanks for your response krilli. Sorry for lack of a response for awhile—I've been incredibly busy.

It looks like for the server I am going to go for a Mac mini (server edition), and do storage externally. This should offer a lot more flexibility down the road, since the storage and the machine can be upgraded independently of each other.

I have been reading up a lot on ZFS with RAIDZ/RAIDZ2, and I have to say it looks really nice, and not too complex. I learned a lot from this one post on ZFS on FreeBSD as a NAS.

I also learned a lot here.

OS wise, it seems like OpenSolaris is what most people are using, although I have seen some people say that OpenSolaris is limited in some ways (not very clear on what) and that FreeBSD is a better option. Any thoughts on this?

As far as raidz vs raidz2, it seems the only difference (?) is that raidz2 is double parity (which protects against two simultaneous drive failures if I understand correctly). If I understand correctly this means that if I wanted to add 1TB more space to an existing pool, I'd need to buy 3 1TB drives—1 for storage, and 2 for parity. Is this correct? Or is it possible to achieve something like the Drobo Pro does, where adding just 1 drive continues to grow available storage while continuing to protect against two simultaneous drive failures?

On another note, it seems that with the Drobo Pro, one can have two sets of hard drives (for example, two sets of 3 x 2TB drives. 6TB on-site, 6TB off-site) that are swapped out of the same Drobo on a regular (e.g. weekly) basis, keeping both sets of drives up to date, and the drives can be re-inserted back into the Drobo in any order. Do you know if this is possible with ZFS?

In terms of the above the Drobo Pro looks like the best solution. With that said, it seems that its achilles heel is poor throughput.

With all this said, I guess my questions are:

• If going down the ZFS road, what's the OS, OpenSolaris, FreeBSD, or something else?
• Is my understanding of raidz2 accurate? Is there no way to add more storage without purchasing three new drives?
• Does ZFS with raidz2 support re-inserting drives in any order, to make swapping out drives on a weekly basis easier? (Sharpy is always an option if not).
• Is there anything in particular I need to know about iSCSI?

Thanks again for all your help.

posted by jesseendahl at 3:48 PM on December 22, 2009

Response by poster: I forgot to mention—I do still want to use the file sharing options built into Mac OS X server to control access to files. Could I simply connect my ZFS box via iSCSI to a gigabit switch, mount the giant volume/pool on the Mac mini, and then share out folders from it via Mac OS X Server, as I do now with normal external hard drives?

Thanks again,

posted by jesseendahl at 3:54 PM on December 22, 2009

Response by poster: For anyone else who might check out this thread in the future: this post on the benefits of ZFS is great.
posted by jesseendahl at 3:58 PM on December 22, 2009

Best answer: Also useful: How I Used Solaris OS and ZFS to Solve My Mac OS X Storage Problem.

This gentleman walks through all of these steps, showing the commands he used along the way:

1. Build a file server.
2. Install the Solaris OS on the file server.
3. Use ZFS and RAID-Z to create a storage pool on the file server.
4. Create folders for my files.
5. Share the folders.
6. Connect to the NFS share from Mac OS X.
7. Copy over files to the file server.
8. Check the file server.
posted by jesseendahl at 4:04 PM on December 22, 2009 [1 favorite]

« Older Help me wrap and present delicious but frozen food...   |   Oil and vinegar, hold the oil. Newer »
This thread is closed to new comments.