Unraid as backup server

I am very happy with my unraid.  We have had our ups and downs,  but in the end she won me over.

I am looking to improve my performance across the (home)network in terms of file transfer speeds.  My current data requirements are:

Media - 6GB

General data (pdf/docs) - 1GB

What I had in mind was this:

1. Purchase an off the shelf NAS

2. Copy all/most files to the NAS.

3. Use the NAS as the main 'working' file server.

4. Backup on a daily / alternate day basis, the NAS to my trusty unraid server.

Questions:

i)  Does this make sense ?

ii) What NAS would you get ?  (Bearing in a mind a 'reasonable' cost/performance ratio).

iii) What software would you use for the backup, to ensure no redundancy ?

I operate PC's and android tablets on my network.

Thanks.

I kind of have to assume your data/docs are 6TB and 1TB respectively.

I don't have any recommendations regarding NAS devices, as the last one I had used a 100mbit connection, so was slower than my unRAID build.

Speed equals money.

If you want faster, you should probably look at FreeNAS or similar. Most "off the shelf" SoHo NAS are not going to deliver much performance increase over unRAID as they are built with component cost as a primary factor.

One of the 4-bay Synology units would work well.    Populate it with 4TB (or larger) drives and you'll have plenty of storage for the requirements you've outlined.

You could also simply build a 2nd UnRAID server with a an SSD cache pool (2 drives).  This would ensure all writes were immediately fault-tolerant; but would also be at network speed, since the actual (slower) array writes would be done overnight.

I'm using a Synology as my online and an unraid as my offline backup.  I use fastcopy to copy (usually a BR ISO) to the unraid and it automatically shuts down the unraid and my PC.    Don't care how fast or slow the unraid system is, just start up the process and walk away.