I'm looking to back up my MacOS computers to my UnRaid server.  My thought was to use rsync, with rsync running on my UnRaid server in "server" mode.  This works except for the lack of the -E (--extended-attributes) flag on the UnRaid side, which prevents me from getting a byte for byte copy of my  MacOS disks.  This article describes how to patch the rsync source and produce a linux binary http://www.oreillynet.com/cs/user/view/cs_msg/66237?page=last with the Apple extensions. I unfortunately do not have a full linux server to build the patched rsync myself.  Has anyone already done this?  Does it work with UnRaid?  Do you have a binary you can share?

I'll check into this, but I believe the "extended attributes" have to also be built into the file system.

I'm reasonably sure that the extended attributes are stored in a file with the same name of the original file but with ._ added on the front, so the destination file system does not need to understand them.  If there is a better/easier way to make "true" backups of a MacOS file system to an UnRaid server please let me know.  Thanks.

Well I got a full Slackware distro installed on a VM and was able to build rsync with exteded-attributes.  It seems to work fine.  I can now do automatic scheduled backups of my macs!