Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I'm a photographer and I have a requirement find a better method of storing my photo library.

Currently I use a Macbook Pro and 6 external drives connected via USB2 or FW800. They are divided up in pairs, one is a copy of the other synced manually with rsync. It's slow.

I am considering building a NAS box and using two 2TB drives with software RAID to mirror the drives, and consolidating my library to one central location that I can access via 1gb lan, or Wireless network when convenient.

I would like to employ FreeNAS as I understand it supports AFP.

I don't know how software RAID works, hoping that at any time I can pull the master drive off and plug it into the macbook via eSATA so I can work with much faster speed... plug it back into the NAS box and have it sync the drives if necessary.

So, I'm seeking the best method and advise on my project. Should I consider FreeNAS or OpenFiler, and what file system should I choose for the drive so it plays nice with OSX when plugged in locally via USB, eSATA or FW800.

Many thanks

share|improve this question
add comment

4 Answers

up vote 2 down vote accepted

I know you're looking for software raid, but I do highly recommend Adaptec SAS HBAs like the SAS-2405. Adaptec works with the FreeBSD community to support their drivers too (FreeNAS is based on FreeBSD). And you can usually pick them up at a reasonable price on eBay. Good hardware RAID will usually beat the pants off software RAID, and may add hot-swap or other features.

That said, there are several ways to mirror a drive in the software. If I remember correctly the web interface only provides one method, the most commonly used, and simplest. For wireless connections it's plenty fast enough. It will not keep up with gigabit ethernet, but may be fast enough for you regardless.

FreeNAS does support AFP; and both FreeNAS and OSX support CIFS (aka SMB) which makes them interoperable with Windows systems. You could also use iSCSI, but I wouldn't recommend doing so.

Pulling drives out of the array constantly is asking for trouble. First off, if you pull the drive and make changes then plug it back in, the array is going to assume those changes are corruptions and overwrite them. You may also introduce stability issues, but data loss from the previous problem is highly probable.

I use FreeBSD daily, so I'm biased to FreeNAS; OpenFiler would works as well though (it's based on Linux). OSX's Darwin base is also based on FreeBSD.

share|improve this answer
    
Thanks for the reply, I understand RAID better now. I'll start on FreeNAS tonight! –  Chris Feb 23 '10 at 15:41
    
I'm going to give this a try - perhaps instead of RAID I will setup an rsync routine to make a day-old copy to another drive. Thanks! –  Chris Feb 25 '10 at 14:49
add comment

That's not how RAID works. Think of it just as a more reliable hard disk. Don't try smarty schemes where you pull and replug drives hoping that it will resync. at least, i will resync in the wrong direction. at worst, it will declare irreconcilable inconsistency and block address to all data.

Also, RAID is no backup. what you have now is a simple backup. if anything fails while writing to the 'primary' disk, you still have the other one. In RAID1, both disks are identical, if something goes wrong in software, it will reliably write the wrong data on both disks.

it's not hard to use two disks to get something (remotely) similar to time machine: one disk has the 'master', and the other one keeps a 'yesterday' copy, with some 'views' of previous states of the data, typically going backwards a week or a month. check rsnapshot; it's a Perl, script it runs on any Unix-like system.

You can even make it the main transfer method, so you have one big disk locally connected to your mac, and use rsnapshot to keep the rolling backup on a network box. This works wonderfully even in medium-sized LANs, easily backing up the important directories of several servers and user's stations.

share|improve this answer
    
RAID1 would work for disk failure, corruption I am (a little) less worried about. However, a valid point. If something gets deleted accidentally, it's gone. Having a day or week old backup I can manually trigger is not a bad idea. Thanks! I will check out rsnapshot, many thanks! –  Chris Feb 23 '10 at 15:43
add comment

For something easy that will keep your data secure and allow you fast access, I would get a Drobo (http://www.drobo.com/products/drobo.php). As the other's said, you will not be able to remove a drive from the raid and use it directly, raid's generally need their other drives to function properly.

That will let you access your files via firewire 800 or usb 2, and if you need network connectivity you can attach a drobo share to it.

share|improve this answer
    
I'm not sure how the Drobo (without the $200 share add-on) solves the problem here. Seems like it would be $400 for no real gain, other than eliiniating a few usb cords. I suppose if he didn't have any hardware to begin with this may be a viable option though. –  Chris S Feb 23 '10 at 21:37
    
I took from his post that he doesn't necessarily have any hardware, and he wants to be able still to plug directly into it for faster than lan access. So, while the Drobo + Drobo share + drives will be fairly expensive, it will be dead simple to setup, provides data redundancy, and he will be able to expand the storage by adding and/or swapping drives. A FreeNAS or OpenFiler solution will involve rebuilding the whole array to expand it (unless I missed something in the way they handle raid), and he will be limited to network only access to a FreeNAS or OpenFiler solution. –  user27787 Feb 23 '10 at 22:45
    
Drobo is a valid option for many. In find it expensive and limiting. I have some hardware, and I think I can build something that fits my requirements better than a drobo - and configure it to do more than a drobo can do. Great suggestion though, especially for an all-in-one solution. –  Chris Feb 25 '10 at 14:48
add comment

If you only have one client accessing the volume at a time (ie: your laptop), I would consider using iSCSI. It is a block-level protocol and will give better performance than AFP, CIFS, or NFS. Your laptop will see the volume as if it were directly connected (as opposed to a network share). I use the globalSAN iSCSI initiator (client) with excellent results.

For further performance, use RAID-0 between the drives. RAID-0 is fast, but doesn't offer any protection if a drive fails, so you have to have a good backup solution in place too. Even if you use RAID-1 or -5 or -6 (which do offer some protection), you need a good backup solution in place.

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.