How To Mirror Data on 2 Separate Drives Within Array

[avp2306]

I'm considering the following UnRaid setup and need a recommendation on how to achieve this as well as some opinions / comments from experienced users.

 

Parity:

         6TB Drive 

Array:

         3 x 2TB Drives for data (Shares will point to these 3 drives)

         + 6TB USB Drive to mirror data (Not selected in any Shares)

 

This may be an uncommon setup, and some folks may say it's redundant but hear me out. My data will fit on 3x 2TB drives, I can setup Shares to use only these 3 drives and I'm OK having UnRaid balance the files and store data whichever way it prefers.

 

However I do want another copy of all of my data on a single 6TB USB drive, this way I can always have access to my data on a single drive, outside of UnRaid, just in case. I also want this USB drive to be protected by parity. 

 

What would be a good way to achieve this?

Edited January 23, 2019 by avp2306

[whitephoenix117]

Just came across this in my search for a similar solution. While I haven't tried it, I think running 2 syncthing instances both pointing to different shares would work for both of our use cases.

 

@avp2306 FYI Unraid array drives are readable outside the array

 

Goals

• Maintain Unraid array flexibility compared /w ZFS (add/ remove drives, different sizes, etc)
• Protect against drive loss
• Protect against bit-rot

Proposed Solution

 

Shares 1 & 2 should be protected by Dynamix File Integrity plug-in

• Array
  • Share 1 (Critical Primary)
    • Disk1
    • Disk2
    • etc
  • Share 2 (Critical Backup)
    • Disk3
    • Disk4
    • etc
  • Share 3 (Non-Critical)
    • All disks

All data, applications, etc would write to Share 1. Syncthing would then be utilized to mirror data between Primary --> Backup. This would also allow for file versioning utilizing sync things own service

 

This would likely be acceptable for my use case as my "critical" data is maybe 10% of my total storage, so disks 3 + 4 in the backup would also be utilized to store other data in the array.

 

Would love some feedback from the Unraid Experts!