使用JZ2440V2板子出现问题该怎么办？

使用JZ2440V2板子出现问题：Root-NFS: Unable to get mountd port number from server, using default
使用uboot 加载 nfs 30000000 192.168.1.101:/work/nfs_root/uImage_nonand     /*uImage_nonand是按照韦老师视频去掉nand驱动部分*/
                          bootm 30000000
出现以下错误，无法挂接根文件系统，奇怪的是不使用uImage_nonand，却能正常挂接NFS根文件系统，请问哪里出错了。
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book@book-desktop:~$ sudo /etc/init.d/nfs restart
sudo: /etc/init.d/nfs: command not found     /*找不到命令，为何*/
book@book-desktop:~$ service portmap status
portmap start/running, process 700
book@book-desktop:~$ service nfs status
nfs: unrecognized service                              /*不成功*/

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sudo service portmap restart
service portmap status
portmap start/running, process 700

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sudo /etc/init.d/nfs-kernel-server restart
book@book-desktop:~$ sudo /etc/init.d/nfs-kernel-server restart
* Stopping NFS kernel daemon
   ...done.
* Unexporting directories for NFS kernel daemon...
   ...done.
* Exporting directories for NFS kernel daemon...
exportfs: No options for /work/nfs_root 192.168.1.: suggest 192.168.1.(sync) to avoid warning
exportfs: /etc/exports [1]: Neither 'subtree_check' or 'no_subtree_check' specified for export "192.168.1.:/work/nfs_root".
  Assuming default behaviour ('no_subtree_check').
  NOTE: this default has changed since nfs-utils version 1.0.x

exportfs: /etc/exports [1]: Neither 'subtree_check' or 'no_subtree_check' specified for export "*:/work/nfs_root".
  Assuming default behaviour ('no_subtree_check').
  NOTE: this default has changed since nfs-utils version 1.0.x

exportfs: No options for /work/nfs_root/first_fs 192.168.1.: suggest 192.168.1.(sync) to avoid warning
exportfs: /etc/exports [2]: Neither 'subtree_check' or 'no_subtree_check' specified for export "192.168.1.:/work/nfs_root/first_fs".
  Assuming default behaviour ('no_subtree_check').
  NOTE: this default has changed since nfs-utils version 1.0.x

exportfs: /etc/exports [2]: Neither 'subtree_check' or 'no_subtree_check' specified for export "*:/work/nfs_root/first_fs".
  Assuming default behaviour ('no_subtree_check').
  NOTE: this default has changed since nfs-utils version 1.0.x

   ...done.
* Starting NFS kernel daemon
   ...done.

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service --status-all信息如下：book@book-desktop:~$ service --status-all [ ? ]  acpi-support [ ? ]  acpid [ ? ]  alsa-utils [ ? ]  anacron [ - ]  appARMor [ ? ]  apport [ ? ]  atd [ ? ]  avahi-daemon [ ? ]  binfmt-support [ - ]  bluetooth [ - ]  bootlogd [ - ]  brltty [ ? ]  console-setup [ ? ]  cron [ + ]  cups [ ? ]  dbus [ ? ]  dmesg [ ? ]  dns-clean [ ? ]  gdm [ - ]  grub-common [ ? ]  gssd [ ? ]  hal [ ? ]  hwclock [ ? ]  hwclock-save [ ? ]  idmapd [ - ]  jetty [ + ]  kerneloops [ ? ]  keyboard-setup [ ? ]  killprocs [ - ]  laptop-mode [ ? ]  module-init-tools [ ? ]  network-manager [ ? ]  networking [ + ]  nfs-kernel-server [ ? ]  ondemand [ ? ]  openbsd-inetd [ ? ]  pcmciautils [ ? ]  portmap [ ? ]  pppd-dns [ ? ]  procps [ + ]  pulseaudio [ ? ]  rc.local [ ? ]  rpc_pipefs [ - ]  rsync [ ? ]  rsyslog [ ? ]  rsyslog-kmsg [ - ]  saned [ ? ]  screen-cleanup [ ? ]  sendsigs [ ? ]  speech-dispatcher [ ? ]  sreadahead [ + ]  ssh [ ? ]  statd [ ? ]  stop-bootlogd [ ? ]  stop-bootlogd-single [ ? ]  udev [ ? ]  udev-finish [ ? ]  udevmonitor [ ? ]  udevtrigger [ ? ]  ufw [ ? ]  umountfs [ ? ]  umountnfs.sh [ ? ]  umountroot [ ? ]  unattended-upgrades [ - ]  urandom [ ? ]  usplash [ + ]  vsftpd [ ? ]  wpa-ifupdown [ - ]  x11-common


--------------------------------------------------------------打印信息-------------------------------------------------------------------------------------------------------------------


OpenJTAG> nfs 30000000 192.168.1.101:/work/nfs_root/uImage_nonand
ERROR: resetting DM9000 -> not responding
dm9000 i/o: 0x20000000, id: 0x90000a46
DM9000: running in 16 bit mode
MAC: 08:00:3e:26:0a:5b
could not establish link
File transfer via NFS from server 192.168.1.101; our IP address is 192.168.1.123
Filename '/work/nfs_root/uImage_nonand'.
Load address: 0x30000000
Loading: #################################################################
         #################################################################
         #################################################################
         #################################################################
         #################################################################
         ####################################
done
Bytes transferred = 1845496 (1c28f8 hex)
OpenJTAG> bootm 30000000
## Booting image at 30000000 ...
   Image Name:   Linux-2.6.22.6
   Created:      2014-07-28  14:55:03 UTC
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    1845432 Bytes =  1.8 MB
   Load Address: 30008000
   Entry Point:  30008000
   Verifying Checksum ... OK
OK

Starting kernel ...

Uncompressing Linux...................................................................................................................... done, booting the kernel.


NET: Registered protocol family 1
drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
eth0: link down
IP-Config: Complete:
      device=eth0, addr=192.168.1.102, mask=255.255.255.0, gw=192.168.1.1,
     host=192.168.1.102, domain=, nis-domain=(none),
     bootserver=192.168.1.101, rootserver=192.168.1.101, rootpath=
Looking up port of RPC 100003/2 on 192.168.1.101
eth0: link up, 100Mbps, full-duplex, lpa 0xC5E1
rPCBind: server 192.168.1.101 not responding, timed out
Root-NFS: Unable to get nfsd port number from server, using default
Looking up port of RPC 100005/1 on 192.168.1.101
rpcbind: server 192.168.1.101 not responding, timed out
Root-NFS: Unable to get mountd port number from server, using default
mount: server 192.168.1.101 not responding, timed out
Root-NFS: Server returned error -5 while mounting /work/nfs_root/first_fs
VFS: Unable to mount root fs via NFS, trying floppy.
VFS: Cannot open root device "nfs" or unknown-block(2,0)
Please append a correct "root=" boot option; here are the available partitions:
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)