How does the Disk Array works?

Hello guys,

i have a problem. I want use unRAID, but without the Disk Array Option.

I can't figure out whats the sense of this Disk Array.

I just want to use unRAID for virtual machines.

Whats the sense behind the Parity Drive? Because im loosing here my biggest HDD and i cant do anything with it.

This will be addressed in a future release.  Our recommendation is to assign just 'disk1'.  You don't have to assign parity or any other disk devices, though ultimately you might find it handy to have a destination to put things, such as VM backups.  For this reason we also recommend setting 'btrfs' as the file system type rather than default 'xfs'.

Okay nice so this means, i dont need any parity device?

I have an external NAS, where i can store my backups

Okay nice so this means, i dont need any parity device?

I have an external NAS, where i can store my backups

Right Parity is not required.  I bet you can't do btrfs incremental backup to your NAS though, right?

I bet you can't do btrfs incremental backup to your NAS though, right?

Just started using this a week ago, incremental backup of my 8 VMs with btrfs send/receive took less than a minute, very nice. 

I bet you can't do btrfs incremental backup to your NAS though, right?

 

Just started using this a week ago, incremental backup of my 8 VMs with btrfs send/receive took less than a minute, very nice. 

Yes we have a VM snapshot/backup utility on the feature plate.  Requires VM subdirs in 'domains' share to be btrfs snapshots instead of actual directories, which requires 'domains' to live on a btrfs volume (which it does for cache pool).  Next requires target volume to receive backups to also be btrfs.  I have an array disk formatted with btrfs for this purpose.

What I have been doing is:

1. Shutdown or Hibernate windows VM.

2. use command line to create snapshot of VM subdir.

3. Restart VM.

4. initiate the 'btrfs send' of the snapshot to backup volume.

Do you follow similar steps?  I'm curious how to backup windows reliably in this manner without shutting down windows, any thoughts on that?

What I have been doing is:

1. Shutdown or Hibernate windows VM.

2. use command line to create snapshot of VM subdir.

3. Restart VM.

4. initiate the 'btrfs send' of the snapshot to backup volume.

 

Do you follow similar steps?  I'm curious how to backup windows reliably in this manner without shutting down windows, any thoughts on that?

This is exactly what I've been doing, I'm using an unassigned disk as destination, look forward to the utility, it's a good idea.

At first I was taking the initial snapshot with the VM running, while it always worked, after further reading I found this is not recommended as the backup will be in a crash consistent state, so now I shut it down just for the snapshot, which takes a second, but if there was a way to safely snapshot with the VM running it would be the perfect solution.

It just came to me that since the live snapshots I've tried were working correctly, and it's not like the VM itself doesn't crash once in a while, from now on I'll be using a script to make daily online snapshots and then send/receive, I'll still do a offline snapshot every time I can, especially when I need to stop the array for another reason, and name them differently so I know which is which, this way and in case I need to restore I'll try to use a backup from an offline snapshot but at least I'll have more options, and I could for example restore a more recent online snap to recover a file or setting and then go back to an older offline snap if possible.

Question for Tom (or anyone else):

When doing send/receive of the daily snapshots I made the script use yesterday's image as parent and send the diff to today's snapshot, I believe as time goes by this should be significantly faster than always using the initial snapshot as parent, although it's only computer time, it seems unnecessary, the end result should be the same, daily snapshot backups.

Is this correct or am I missing something and should always send the diff from the initial snapshot to today's?