Linux – How to get NFS on Linux to export a folder to OS X with OS X’s user IDs so I can cp -a from Linux to OS X

I have Ubuntu GNOME 15.10 on one computer and OS X 10.11.2 on another. I want to migrate files from the Ubuntu installation to the OS X installation but preserving permissions.

Currently the strategy I am attempting is to export my home directory over NFS, mount it from the Mac, and cp -a the files off the mount. I know that on OS X UIDs and GIDs are assigned differently than on Linux. On Linux my UID/GID is 1000/1000 and on OS X my UID/GID is 501/20.

From what I can gather, having this in my /etc/exports should be sufficient to get my Linux files showing up as 501/20 on the Mac:

/home/pietro/   <Mac's IP>(rw,sync,all_squash,no_subtree_check,insecure,anonuid=501,anongid=20)

and mounting on the Mac with

mkdir /tmp/q
sudo mount -t nfs <Linux's IP>:/home/pietro /tmp/q

However, when I mount this way, ls -l on the Mac tells me that the file permissions are still 1000/1000.

I have also tried:

• no_root_squash
• anonuid=1000,anongid=1000
• removing no_subtree_check
• removing sync
• echo N | sudo tee /sys/module/nfs/parameters/nfs4_disable_idmapping followed by sudo nfsidmap -c
• NEED_IDMAPD=yes in /etc/default/nfs-common
• -o resvport on the Mac

all to no avail.

So my question is: how do I configure NFS so that when I ls -l on the Mac side I get 501/20 as the owner/group, so I can safely cp -a?

Alternatively, am I using the wrong tool for the job and is there a better way? I need to preserve the other Unix permissions, so SMB does not seem to be an option. I'm also unwilling to risk changing the UID/GID of the OS X account.

Thanks.