I have a FreeBSD NFS server with a mount, say '/mnt', and some mount points within it, say '/mnt/Documents'. When I mount from CentOS 7, the submounts are mounted automatically:
# mount -t nfs4 -o soft,intr 10.0.0.1:/mnt nfs-test # ls nfs-test/Documents stuff
whereas on Fedora:
# mount -t nfs4 -o soft,intr 10.0.0.1:/mnt nfs-test # ls nfs-test/Documents ls: reading directory nfs-test/Documents: Input/output error
likewise, if I mount this submount separately, the mount succeeds but I get the same error when I try to read the directory. If I try to mount the submount within the existing parent NFS mount:
mount.nfs4: /home/_/nfs-test/Documents is busy or already mounted
The fact that it works under CentOS leads me to believe there isn't a configuration issue on the server side, but I can provide details about that if necessary.
Please let me know whatever additional details are desired.