What is a better option for me?

[William Yeo]

I'm currently planning to buy/build a NAS in the coming few days.
I had initially set my eyes on the Synology DS412+ until i read abt FreeNAS few days ago.

Below are the usage for the NAS:

1. Converting desktop to M-ITX/M-ATX
2. Storage/backup of pictures and videos
3. Streaming of HD video to anywhere within my house
4. Centralised server for content extraction

Currently i'm planning to use the HDD in my current rig.
1TB x 2
2TB x 2

Is it a better choice to get a HP N54L and use FreeNAS? or just buy a DS412+?
Intend to run on Raid5

 

[goudviske]

personally i'd always go for DIY nas implementations, because they are a lot more flexible, and because (if you know what you're doing) you have more options and a better idea of what's wrong when (not if, only a matter of time) something goes wrong.

on the downside, this does require some reading up, maybe some testing, and some general background sense of IT won't hurt either.

if you want to invest some time in setting it up, then absolutely go for a freenas or similar installation, if you think you don't have the time, or you don't want to invest the time, then i'd go for a synology/qnap/... thingy.

one more note, you mention you want to run R5, I would not recommend doing that with the hard drives you list, look up raid5 on wikipedia for better info, but with 2x2 TB and 2x1 TB your raid 5 array would only be 3 TB (unformated), it scales down to the smallest disk. with the hard drives listed I would go for Raid10 (2x 1 TB in mirror and 2x 2 TB in mirror, then striping those arrays), you would also only get 3 tb, but it will be faster and more reliable. another option would be to stripe the 2 x 1 TB first, and then make a R5 (or raidz) of 3 x 2 TB, and this will give you 4 TB usable.

if what you 're reading here sounds like chinese, you need to do some reading,don't overestimate the complexity, it really isn't that hard, but it's important you get your basics right, so you know where and how your data is stored.

 

[gpsguy]

I would never recommend that option.

It gives one the perception that one can lose a drive in the array, but if the failed drive is one of the disks in the stripe, the pool is lost.

another option would be to stripe the 2 x 1 TB first, and then make a R5 (or raidz) of 3 x 2 TB, and this will give you 4 TB usable.

 

[goudviske]

Well I wouldn't use the approach myself either, but given the hard drives at hand, it is an option worth considering.
Also I don't believe the pool would be lost if 1 x 1TB disk would die, actually they could both die and still retain all data, because they are in a R5 with the 2 other 2 TB disks. The stripe is just usefull to "convert" the 2 x 1 TB into 1 x 2 TB volume

At least that's my interpretation, and how I believe it works, haven't tested this on real live machines

 

[Dusan]

Also I don't believe the pool would be lost if 1 x 1TB disk would die, actually they could both die and still retain all data, because they are in a R5 with the 2 other 2 TB disks. The stripe is just usefull to "convert" the 2 x 1 TB into 1 x 2 TB volume

Such configuration is not possible with ZFS. ZFS doesn't support nested virtual devices -- e.g. you can't create a mirror of mirrors or a raidz of mirrors. A mirror or raidz vdev can only contain disks (or files).

 

[goudviske]

Such configuration is not possible with ZFS. ZFS doesn't support nested virtual devices -- e.g. you can't create a mirror of mirrors or a raidz of mirrors. A mirror or raidz vdev can only contain disks (or files).

Can't confirm that,
but you could use the onboard raid controller to make the stripe, so the OS sees it as one drive

 

[Dusan]

Can't confirm that,

http://www.freebsd.org/cgi/man.cgi?query=zpool
Read the Virtual Devices (vdevs) section especially the 2 paragraphs below the list of supported virtual devices.

 

[William Yeo]

Is the something like the SHR on the Synology?