Linux：showmount -e 188.131.xx.xx Timeclnt_create：RPC：プログラムが登録されていません

在nfs服务端执行rpcbind和nfs重启，要按顺序

[root@VM-0-7-centos nfstestdir]# systemctl stop rpcbind
Warning: Stopping rpcbind.service, but it can still be activated by:
  rpcbind.socket
[root@VM-0-7-centos nfstestdir]# systemctl stop nfs
[root@VM-0-7-centos nfstestdir]# systemctl start rpcbind
[root@VM-0-7-centos nfstestdir]# systemctl start nfs