topic Re: Cannot NFS export as rw and root at the same time in Network and Storage Protocols

Cannot NFS export as rw and root at the same time

JERONIMO123 — Thu, 05 Jun 2025 05:34:17 GMT

Hi,

When I have this in the etc/exports file:

/vol/test -sec=sys,rw=1.2.3.4,root=1.2.3.5,nosuid

I cannot mount the volume on host 1.2.3.5:

mount.nfs: access denied by server while mounting 1.2.3.1:/vol/test

When I change the exports to have:

/vol/test -sec=sys,rw,root=1.2.3.5,nosuid

everything works fine. But I don't want everyone to be rw.

(Yes, I'm doing exportfs -r each time after changing the exports file)

Why would that be?

Thanks.

Re: Cannot NFS export as rw and root at the same time

billshaffer — Mon, 16 Jun 2014 19:10:43 GMT

root= does not imply rw= or ro=. For every entry in root=, you need to specify that it can mount the volume (with rw=/ro=). So:

/vol/test -sec=sys, rw=1.2.3.4:1.2.3.5, root=1.2.3.5, nosuid

Bill

Re: Cannot NFS export as rw and root at the same time

aborzenkov — Mon, 16 Jun 2014 19:24:40 GMT

Who is allowed to mount is determined by options rw or ro. Your first command line explicitly denies host 1.2.3.5.

Re: Cannot NFS export as rw and root at the same time

JERONIMO123 — Mon, 16 Jun 2014 21:17:18 GMT

Simple answer to a simple question, thanks.

Would have been even simpler if that was clearly stated in man na_exports or na_exportfs, .... or I just looked in the wrong place for that info.

Re: Cannot NFS export as rw and root at the same time

billshaffer — Mon, 16 Jun 2014 21:40:06 GMT

It kind of says so -

Unlike in Data ONTAP releases prior to 6.5, if you spec-

ify a list of NFS clients with read-write access using

the rw= option, Data ONTAP does not use the ro option as

the default for all other NFS clients.

This was a pretty big deal when upgrading to 6.5, because the exports had to be scoured to make sure required mount ability wasn't going to go away - which is probably why it sticks in my mind....

Bill

Re: Cannot NFS export as rw and root at the same time

JERONIMO123 — Mon, 16 Jun 2014 22:06:36 GMT

Yeah I read that.

But it doesn't help if you don't know that there is 'rw' or 'ro' and apart from that optionally the root parameter, so you have in fact five possible access combinations:

- rw+root

- ro+root

- rw

- ro

- nothing (whether with or without root makes no difference as we have seen)

Well now I know and it will never leave my mind 😉