NFS mount yields: RPC: failed to contact portmap

I do most of my embedded software development whilst running from an NFS mounted root directory. I was therefore rather confused when I was unable to mount a different path on the same server. The following just appeared very slowly:

~# mount server:/path /mnt
portmap: server localhost not responding, timed out
RPC: failed to contact portmap (errno -5).
portmap: server localhost not responding, timed out
RPC: failed to contact portmap (errno -5).
lockd_up: makesock failed, error=-5
portmap: server localhost not responding, timed out
RPC: failed to contact portmap (errno -5).
mount: Mounting server:/path on /mnt failed: Input/output error

The cause is simple. My device isn't running a port mapper daemon. But why should I run such a daemon? The kernel can mount my root filesystem without one!

In order to mount the filesystem the kernel is trying to talk to the local port mapper daemon in order to find the local lock daemon - I don't have one of those either. The problem can easily be fixed by passing “-o nolock”

~# mount -o nolock server:/path /mnt