R o o t F i l e S y s t e m T y p e s

Root File System Types

C H A P T E R

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The following describes the different possibilities which can be used as root file system. The type of rootfs must be passed as an argument to kernel by means of the bootargs environment variable of U-Boot.

NFSROOT

The rootfs may be in a different computer on the network and not within the target. This can be useful if, for example, a RAM disk is too small to include all the necessary files, or allow rapid turnaround during testing and development.

An NFS root allows quick kernel downloads, helps ensure file system integrity (since the server is basically impervious to crashes by the client), and provides virtually infinite storage.

During development it feel free to use an NFS directory as root file system. This avoids unnecessary flash erases, which on a power failure will result in the need to re-program the kernel into flash. It also increases the lifetime of the module because the flash has a limited number of erase cycles. Initialization scripts may be quickly modified since a failure will not result in an unusable system. Initialization scripts can be fixed on the host then reset the target.

The root file system can be installed to "/exports/BOOTDIR" issuing this command in the project directory

$ make install-nfsroot

To test the new image run the following command at the U-Boot prompt in your target:

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Digi 9P 9360/9750 manual Root File System Types