当centos 系统禁用IPV6 之后，开启NFS 是会提示以下错误：
# /etc/init.d/nfs start
Starting NFS services: [ OK ]
Starting NFS mountd: rpc.mountd: svc_tli_create: could not open connection for udp6
rpc.mountd: svc_tli_create: could not open connection for tcp6
rpc.mountd: svc_tli_create: could not open connection for udp6
rpc.mountd: svc_tli_create: could not open connection for tcp6
rpc.mountd: svc_tli_create: could not open connection for udp6
rpc.mountd: svc_tli_create: could not open connection for tcp6
[FAILED]
Starting NFS daemon: rpc.nfsd: writing fd to kernel failed: errno 111 (Connection refused)
rpc.nfsd: address family inet6 not supported by protocol TCP
rpc.nfsd: unable to set any sockets for nfsd
[FAILED]
根据启动提示可以获知，inet6地址不被支持，原因是当前主机没有加载ipv6的模块，可以重新加载一遍ipv6模块解决这个问题。
由于我的系统不需要ipv6的支持，可以通过下面的操作，取消NFS的ipv6调用: 注掉 udp6,tcp6后重启nfs。
# cat /etc/netconfig
#
# The network configuration file. This file is currently only used in
# conjunction with the TI-RPC code in the libtirpc library.
#
# Entries consist of:
#
# <network_id> <semantics> <flags> <protofamily> <protoname> \
# <device> <nametoaddr_libs>
#
# The <device> and <nametoaddr_libs> fields are always empty in this
# implementation.
#
udp tpi_clts v inet udp - -
tcp tpi_cots_ord v inet tcp - -
#udp6 tpi_clts v inet6 udp - -
#tcp6 tpi_cots_ord v inet6 tcp - -
rawip tpi_raw - inet - - -
local tpi_cots_ord - loopback - - -
unix tpi_cots_ord - loopback - - -
启动之后还是报错:
# /etc/init.d/nfs start
Starting NFS services: [ OK ]
Starting NFS mountd: [FAILED]
Starting NFS daemon: rpc.nfsd: writing fd to kernel failed: errno 111 (Connection refused)
rpc.nfsd: unable to set any sockets for nfsd
[FAILED]
启动rpcbin:
# /etc/init.d/rpcbind restart
Stopping rpcbind: [FAILED]
Starting rpcbind: [ OK
再启动NFS :
# /etc/init.d/nfs start
Starting NFS services: [ OK ]
Starting NFS mountd: [ OK ]
Starting NFS daemon: [ OK ]
Starting RPC idmapd: [ OK ]
