Hi everyone. Is FreeNAS for me?

[jsowoc]

I read an article comparing various "for-free" NAS solutions, and FreeNAS came out quite well if you are willing to spend the time researching/configuring it. I want to make a home NAS, and is FreeNAS for me?

I have existing 500GB, 750GB, and 1TB hard drives (1 of each) on which I have my photos, some home videos, and other stuff that I would like to preserve; a RAIDed NAS solution seemed better than simply keeping 3 copies. My main concern is data integrity over availability or performance, but I don't have thousands of dollars for a high-end storage server.

My first idea for a solution was to buy a 1.5TB drive and a 2TB drive and put them all into a 5-disk software RAID6 on a Linux box. This would allow me to grow the (ext4) partition as I eventually replace the 500GB drive with a 3TB, the 750GB with a 4TB etc. Unfortunately, this solution would not protect the data from silent corruption, so that is why I started looking at something ZFS-ish.

I know that I can't change the number of disks (columns) to RAIDZ/RAIDZ2, but can I use non-identical drives? Just like I could iteratively swap out 1TB drives for 2TB drives, can I swap out the smallest drive for a larger one "growing" the file-system? These seem to be my two main concerns before jumping onto FreeNAS.

 

[Durkatlon]

You can't currently grow an existing VDEV by swapping bigger drives into it. This is not supported by the version of ZFS that is used right now in FreeBSD8.2 (and by extension FreeNAS8). Note that RAID is not backup!! With ZFS you stand a much better change of discovering drive errors than other file systems, but for important data it's still key to have a real backup (i.e. on a separate device).

 

[jsowoc]

You can't currently grow an existing VDEV by swapping bigger drives into it. This is not supported by the version of ZFS that is used right now in FreeBSD8.2 (and by extension FreeNAS8).

I read in a few FreeNAS places that this is (was?) possible. For example, the post (referring to FreeNAS 0.7):
http://sourceforge.net/apps/phpbb/freenas/viewtopic.php?f=38&p=14421&st=0&sk=t&sd=a

Note that RAID is not backup!! With ZFS you stand a much better change of discovering drive errors than other file systems, but for important data it's still key to have a real backup (i.e. on a separate device).

I am aware that RAID != backup. I burn all my important things onto DVDs with corresponding recovery data, which I then store in a different part of town.

My concern is that I've always assumed that the data on my hard drives is correct until it catastrophically fails, and was hoping somethings like ZFS would help guarantee that.

 

[ProtoSD]

You can't currently grow an existing VDEV by swapping bigger drives into it. This is not supported by the version of ZFS that is used right now in FreeBSD8.2 (and by extension FreeNAS8).

Actually somewhere here in the forums someone tested this and proved that it was possible. You're correct that the 'Autoexpand' flag/feature isn't available, but according to the poster, the vdev did increase after replace the final disk with a larger one and letting it resilver.

@jsowoc, keep in mind when you mix disks of different sizes in a raidz config, your volume will only be as big as the smallest disk.

 

[jsowoc]

@jsowoc, keep in mind when you mix disks of different sizes in a raidz config, your volume will only be as big as the smallest disk.

You do mean a multiple of the smallest disk, right? If I have 5 drives in RAIDZ2: 500GB, 750GB, 1TB, etc., then I will have a volume size of (5-2)*500GB = 1.5TB.

Thank you for the warm welcome and helpful replies. I think FreeNAS is what I need.