我正在尝试严格按照本教程在 Ubuntu 14.04 中创建 NFS 共享：https://help.ubuntu.com/community/SettingUpNFSHowTo。
root@srv:~# service nfs-kernel-server start
* Exporting directories for NFS kernel daemon... [ OK ]
* Starting NFS kernel daemon [fail]
在syslog中可以看到如下内容：
Feb 5 14:22:53 srv kernel: [37884.636698] nfsd: last server has exited, flushing export cache
Feb 5 14:22:54 srv kernel: [37885.684132] NFSD: Using /var/lib/nfs/v4recovery as the NFSv4 state recovery directory
Feb 5 14:22:54 srv kernel: [37885.684146] NFSD: starting 90-second grace period (net ffffffff81cd3700)
Feb 5 14:22:54 srv rpc.mountd[14901]: mountd: could not create listeners
如何找到原因并成功运行 NFS 服务器？