mount: failed: unknown nfs status return value: -1

Symptom

You are mounting an NFS server filesystem but encountered below error,

# mount 192.16.10:/home/aracici/ itsiti/
mount: 192.16.10:/home/aracici/ failed, reason given by server: 
unknown nfs status return value: -1

Solution

1. Ensure hostname, IP address are maintained on both NFS client and server.

grep HOSTNAME /etc/hosts

2. Ensure the filesystem, hostname, IP address are exported.

showmount -e HOSTNAME