Owners manual

4 Supported File Systems
Linux Software Developers Kit (SDK) User Guide 30
All details can be found in <install-dir>/linux/linux-
2.6.x/Documentation/filesystems/nfsroot.txt
There are a few onetime steps involved to enable this mode as identified below:
µClinux kernel configuration
CONFIG_ROOT_NFS needs to be enabled in the kernel configuration. If a BOOTP or DHCP server
is available on your network you might want to enable CONFIG_IP_PNP_BOOTP or
CONFIG_IP_PNP_DHCP as well.
dBUG Configuration
Within dBUG, the kernel command line kcl needs to be set for NFS.
You have 2 options: use a fixed IP address or enable DHCP or BOOTP in the kernel.


Static IP
For example, if one of the host network cards is configured with an IP of 192.168.3.1 and the
SDK is installed under <install-dir>/, then the target IP should be 192.168.3.88. Set the kcl using
the following command:
NOTE:
The following code must be entered as one line.
dBUG> set kcl noinitrd rw root=/dev/nfs
ip=192.168.3.88:255.255.0.0:192.168.3.1:::eth0
nfsroot=192.168.3.1:<install-dir>/linux/nfs


Dynamic IP
If a DHCP server is running on host, it can be used by performing the following:
1. Enable CONFIG_IP_PNP_DHCP in the kernel.
2. Set kcl noinitrd rw root=/dev/nfs ip=bootp
nfsroot=192.168.3.1:<install-dir>/linux/nfs
NOTE:
The preceding code must be entered as one line.
Host Configuration
In order for the build process to produce a file system that can be mounted via NFS, the
developer needs to manually create a directory named 'nfs' in <install-dir>. This is the trigger for
the build process to create the NFS-mountable directory structure. The user will also need sudo
permissions without having to provide a password as described in Chapter 2:
Installing the SDK
.
On the host machine, NFS server support needs to be installed and enabled. The
<install-dir> needs to be made accessible via NFS by explicitly exporting it. This can be
done with a line like
install-dir>/linux 192.168.0.0/255.255.0.0(rw, no_root_squash,
anonuid=500,anongid=500,insecure,sync,no_subtree_check)
in /etc/exports