NBDST(8) System Manager's Manual NBDST(8)

nbdst — NetBoot deferred shadow tool

nbdst [-recycle | -preallocate size] devnode shadowfile

nbdst is used during NetBoot to associate a shadow file with the disk image being used as the root device. After the shadow file is attached, subsequent writes to the root device will be redirected to the shadow file, which normally resides on local storage. nbdst is invoked by /etc/rc.netboot

The following arguments must be specified:

devnode
The device node of the root device, in the form "disk0"
shadowfile
Path to a shadow file which will be created and associated with the NetBoot root device

If a shadow file already exists, reset it and use it again. Otherwise, information written to an existing shadow file will reappear. Reusing a previous shadow file without resetting it requires that the shadow file be created with the same base image.
size
Set the shadow file to the given size up front. This forces a reset of the shadow file (like -recycle).

nbdst can only be run as root.

hdiutil(1), hdik(8)

29 Apr 2003 macOS