[systemd-devel] howto migrate some things to systemd

[Robert Schwebel]

On Sat, Apr 16, 2011 at 08:41:07PM -1200, Kajikawa Jeremy wrote:
> I believe you can pre-set the systemd configuration for the target
> system,
>
> build and install systemd as you would anything else...
>
> but configure systemd to run with a read-only fs and deliberately
> "mount -t tmpfs <device> <mountpount> -o size=128MB" Â  to provide
> some read-write space is what I would think to do...
>
> that way even with the one-time stuff it can be repeated on occasion
> without any real trickery being performed.

What Michael does within ptxdist [1] is that he builds a root filesystem
for embedded systems. Ptxdist outputs a completely compiletime built
root filesystem image which is then flashed into the device, i.e. in a
production scenario into hundrets or thousands of devices.

When these devices are then booted for the first time, they do things
like generating an SSH host key, which is then stored into the system.
Or, for quickboot scenarios, it does an automatic prelinking of all
binaries.

This kind of actions makes it necessary that you have access to the
rootfilesystem itself, not only to some temporary ramdisk.

rsc

[1] http://www.ptxdist.org
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