nfs can't mount Permission denied

:localhost:root > mount 10.224.193.55:/wwwdev /www
mount: 10.224.193.55:/wwwdev failed, reason given by server: Permission denied

原因：

排除iptables防火墙、hosts.deny限制等原因，子网内所有服务器都有权限mount,
showmount -e 10.168.1.162
/data/iscsi/webapp  10.168.1.0/24
考虑是否超出了nfs服务器支持的客户端数量上限。查资料nfs属于无状态服务，没有数量限制。试过多种方法，终于解决，只要mount
nfsd on /proc/fs/nfsd type nfsd (rw)

you can solve the problem adding the following lines in /etc/fstab on the server side:

nfsd /proc/fs/nfsd nfsd auto,defaults 0 0
sunrpc /var/lib/nfs/rpc_pipefs rpc_pipefs auto,defaults 0 0

Then type on the server
mount -a

And try to mount de resource in the client

解决：

nfs server:

UNKNOWN:msj1mcs102:log # more /etc/fstab

nfsd                    /proc/fs/nfsd           nfsd    auto,defaults   0 0
sunrpc                  /var/lib/nfs/rpc_pipefs rpc_pipefs auto,defaults 0 0

UNKNOWN:msj1mcs102:log # mount -a

client:

:localhost:root > mount 10.224.193.55:/wwwdev /www