I am troubleshooting the NFS export permission. I have exported a volume with option -sec=sys,rw=192.168.10.0/24, and it is successfully mounted from a linux clinet in the network 192.168.10.0/24. The client can perform list and read existent file but cannot create or modify any file in the NFS mountpoint, despite the account I used to mount the NFS export from the client. This problem can be solved by using the export option -sec=sys,rw=192.168.10.0/24,root=192.168.10.0/24.
I did some search in google and this community and learnt in most situations, volumes are exported with rw option AS WELL AS root option together. Specifying root option is like specifying no_root_squash in ordinary linux as an NFS server. However, I wonder if there is a situation where we use only rw option to export a volume? Without specifying root option, does the rw option basically equal to the ro option?