I did more debgging and research. It seems to me the problem (only on aarch64) only happens when a process is no longer root. So like when polkit changes to the polkitd user, then it is unable to access files. This is supported by me making a local user in root image. I cannot su to that user no matter what. ("Operation not supported"). However, if I get rid of the overlay and just use the read-only mount vers3 nfs point, I can chroot in to it and su to the user just fine. So this problem only happens with a combination of: - Ganesha NFS (kernel nfs, gluster NFS ok) - rhel76 aarch64 client (x86_64 rhel76 client ok) - overlay kernel module doing a union The other combinations work. Note that I haven't tried other Linux distros in any part of the solution yet. I seem to be stuck in the inconvenient place of being in a corner case without the experience to get myself out :( There is some interaction of x86_64 + overlayfs + ganesha that fails related to file permissions for non-root users. :( I'm not sure how much further I can dive in to this on my own but I'll try to think of some things to look at. Erik