Force NFS v3 Mounts
(2014-07-17)
Problem
My CentOS 6 client is trying to mount everything using NFS v4 and I want it to use v3.
Solution
Change /etc/sysconfig/autofs:
# Turn off v4 protocol support
RPCNFSDARGS="-N 4"
Change /etc/nfsmount.conf:
# Protocol Version [2,3,4]
# This defines the default protocol version which will
# be used to start the negotiation with the server.
Defaultvers=3
#
# Setting this option makes it mandatory the server supports the
# given version. The mount will fail if the given version is
# not support by the server.
Nfsvers=3
Restart or reboot and you should be good to go.
(Note: this is a poor substitute for setting up NFSv4 properly.)