zfsonlinux or rsync for Backup and Linux sharing

[Martin RR]

Hi everybody,

I am using some USB disk for backup.
And I would like to use them with FreeNAS and Linux.

So my question is it really safe to use a ZFS pool created within Linux (zfsonlinux.org) and copy my files.
I tested it and works, but I am not 100% sure. I did not need the latest ZFS features, I just would like to keep my data safe.

Or should I use rsync.

 

[nojohnny101]

so you want to backup your freenas box to a USB drive you have?

search the forums, this has been covered before. short of it is, probably the most safe way to do it is to connect the USB drive to a computer and then rsync to it.

 

[Martin RR]

Hi Johnny,

thanks. I read some posts in the forum e.g.
https://www.google.com/url?q=https:...ds-cse&usg=AFQjCNFwKJ4E_oM7WYckAFZrrf24ZDy1sQ

But I most comments are that you should not use it. But zfsonlinux got a lot updates, and I could verify that I can import the pool without problems in Freenas 9.10.
But are there still some drawbacks. I would prefer to have backups on disk with zfs (zfsonlinux) and esata disks, rather than rsync via LAN.
So does anyone have advise / experience / problems with recent zfsonlinux and import/export/copy of these pools in FreeNAS?

Thanks a lot.

 

[nojohnny101]

so you want to backup your freenas box to a USB drive you have?

^^answer this first so I can understand what you want to do.

I can't speak to zfsonlinux's computability with FreeNAS but I suspect there is an easier way to do what you want to do if I just knew what you wanted to do.

 

[Martin RR]

Yes, I want to backup to an external drive via esata / sata-multiplier. And I would like to use this disk(s) not only for backup reasons, but also use them with Linux (other PCs).
So my idea was to use zfs for this.

IMHO, everything should be ok/safe with the latest version of zfsonlinux, because the zpools use the same pool version and features (ZFS pool version 5000).

But the questions still arise:
a) should the pools created within FreeNAS or Linux (currently created the pool on a linux and I can export/import the pool in FreeNAS/Linux)
b) If export/import works, might there any risk or safety issues.

I created a pool on Linux, Imported it in FreeNAS and copied about 4TB of data (FreeNAS). And I can access the pool/data again in Linux.

But is this a safe way, good idea?

 

[Martin RR]

FreeNAS is using the ZFS FreeBSD implementation, so everything should be fine, as long as the features sets are same. This is the reason, why I created the pool with zfsonlinux and I did not upgrade the pool in FreeNAS. So according to open-zfs.org, everything should be fine.

What are you experience, advise?


http://open-zfs.org/wiki/FAQ

"Compatibility
Are storage pools created by OpenZFS portable between operating systems?
Pools can be moved freely between different implementations of OpenZFS wherever the implementations support the same feature flags.

You can disable a feature flag for a pool when the pool is created. This may be appropriate if you expect to use the pool with a different implementation that does not support the feature.

To maintain compatibility, new feature flags are usually ported to all operating systems very quickly.

Just one pool version is associated with feature flags: version 5000. Versions less than 5000 can not use feature flags."