exportfs returns zero exit status when fails to resolve hostname of NFS client

Issue

• exportfs returns zero exit status when failed to resolve hostname of NFS client.

# cat /etc/exports
/home/nfs-srv7 *(rw,no_root_squash,sync)
/home/harry  test.abcd.efgh.ijkl(rw,no_root_squash,sync)

# exportfs -avr
exportfs: Failed to resolve test.abcd.efgh.ijkl 
exportfs: Failed to resolve test.abcd.efgh.ijkl 
exporting *:/home/nfs-srv7

# echo $?
0