1.clnt_create: RPC: Port mapper failure - Unable to receive: errno 111 (Connection refused)
客户端挂载问题！需要关闭服务端和客户端防火墙以及selinux。
[root@lsx03 ~]# showmount -e 192.168.1.12 //测试有没有挂载的权限
clnt_create: RPC: Port mapper failure - Unable to receive: errno 111 (Connection refused)
第一种：先启动rpc服务，在启动nfs服务
服务器端开启防火墙或者做了设置。出现这种情况。
排查方式：可以客户端telnet 服务端 111端口不通
服务端showmount自己通的话配置没问题

2.exportfs -arv
exportfs: No options for /home/nfstestdir : suggest (sync) to avoid warning
exportfs: No options for 192.168.222.0/24(rw,sync,all_squash,anonuid=1001,anongid=1001) : suggest (sync) to avoid warning
exporting :192.168.222.0/24(rw,sync,all_squash,anonuid=1001,anongid=1001)
exportfs: Failed to stat 192.168.222.0/24(rw,sync,all_squash,anonuid=1001,anongid=1001): No such file or directory
exporting :/home/nfstestdir
解决办法：
192.168.133.0/24(rw,sync,all_squash,anonuid=1000,anongid=1000) //必须写在一行