Backing up data with POSIX ACLs to a FreeNAS share

[JC Denton]

Hello all,

I just purchased and setup my first FreeNAS Mini and I'm uncomfortably excited :)

One of my use cases for a NAS is backing up several of my Linux hosts via rsnapshot using rsync. A few of these machines implement POSIX ACLs, which I understand are only supported under Linux's version of ZFS. I was thinking the way to get around this limitation was to use rsync's "--fake-super" option and store the ACLs in an extended attribute (xattr), but those don't appear to be supported under FreeBSD? So now I'm really scratching my head as to how to get the ACLs backed up. Is the best option just to create a container on the share with another filesystem?

Hoping the FreeNAS sages can help me on this one...

Thanks in advance!

 

[dlavigne]

Were you able to find the solution for this?

 

[JC Denton]

Were you able to find the solution for this?

I debated using an "ext" container, but that felt like it might be more maintenance prone than necessary. So I ultimately ended up setting rsnapshot to run a pre and post sync recursive getfacl/getfattr that's stored just outside of the backup root directory.

I hope xattr support for ZFS under FreeBSD comes soon. I'd even be happy with POSIX ACLs, since both features are currently supported under ZFS for Linux.

 

[anodos]

I debated using an "ext" container, but that felt like it might be more maintenance prone than necessary. So I ultimately ended up setting rsnapshot to run a pre and post sync recursive getfacl/getfattr that's stored just outside of the backup root directory.

I hope xattr support for ZFS under FreeBSD comes soon. I'd even be happy with POSIX ACLs, since both features are currently supported under ZFS for Linux.

FreeBSD has xattr support. Samba uses them to store dos attributes (hidden, system, etc) and alternate datastreams.

How are posix acls being used? I.e permissions for samba share? ZFS supports nfsv4 acls.

 

[JC Denton]

FreeBSD has xattr support. Samba uses them to store dos attributes (hidden, system, etc) and alternate datastreams.

How are posix acls being used? I.e permissions for samba share? ZFS supports nfsv4 acls.

Not for ZFS. When you try to enable them, it complains they're not supported.

No, they're mostly used as ACLs for Apache, users modifying each other's (selective) files, etc. I wish NFSv4/Rich ACLs were supported natively on Linux.

 

[dlavigne]

Yup, https://www.freebsd.org/cgi/man.cgi?query=zfs is pretty clear and is still showing this for 11-CURRENT:

The xattr property is currently not supported on FreeBSD.

It may be worth putting in a feature request at bugs.freenas.org (though you may be redirected to also do that upstream). If you create a request, post the issue number here.