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Using linkbacks

Linkbacks are the primary technique for defining variant configurations between nodes. A linkback causes a file or directory to become a link into the oneSIS RAM disk, which can then point back to a target in the master image based on a node's class or hostname.

A linkback can have several potential targets. The `CLASS' target causes the linkback to point back to the original filename appended with an extension that is the name of the node class as determined by the NODECLASS directives. Similarly, the `NODE' target causes the final target to point back to the original filename appended with an extension that is the hostname of the node.

A linkback target can also be any arbitrary pathname. This target path will be interpolated to replace any instance of `$CLASS' and `$NODE' with the class name and hostname of the node, respectively.

Note: Some files cannot have linkbacks created for them for various reasons. The most notable of these are /etc/inittab, /boot/grub/menu.lst, /etc/mtab, and /etc/sysimage.conf.



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root 2005-06-19