NFS server

Tested with the following operating systems

Installation


user@ubuntu:~$ sudo apt-get install nfs-kernel-server


Example Configuration for NFS boot


Create a directory on the host root filesystem. 

user@ubuntu:~$ sudo mkdir /nfs
user@ubuntu:~$ sudo chmod 777 /nfs

Extract the content of root.tgz to your nfs directory.
root.tgz is located in: 

user@ubuntu:~$ cd /nfs
user@ubuntu:~$ sudo tar -xvf ~/workspace/TQMaxx-BSP-REV.xxxx/platform-MBaxx/images/root.tgz

Next step is to configure the /etc/exports file. Create an entry that contains the path to your nfs folder created above. 

<path/to/your/nfs/directory>       <permitted IPs>/<subnet>(<comma separated options>)

For example

After the /etc/exports file was modified the NFS server need to be restarted: 
user@ubuntu:~$ sudo service nfs-kernel-server restart

Test the configuration


With the command showmount you can see the exported directories. 

user@ubuntu:~$ showmount -e localhost
Export list for localhost:
/nfs 192.168.0.0/255.255.0.0


Troubleshooting


If the root file system cannot be mounted via NFS the log file of the NFS server should be checked. In Ubuntu the log is written to the file /var/log/syslog.

An example of such a log entry looks like: 

Nov 14 02:30:57 ubuntu mountd[8667]: refused mount request from 172.21.10.157 for /opt/ltib_iMX35/ltib/rootfs (/opt/ltib_iMX35/ltib/rootfs): unmatched host

In this case the server rejects the connection because the host does not match the one in the file /etc/exports.

Sources