I know that this is not the usual answer to that sort of question but....
you should try buildroot, rather than base yourself on debian.
When you deactivate the kernel and busybox (it's done through a
menuconfig type interface) you will get the minimal type of system you want.
On 29/08/2018 12:24, Wojtek Swiatek wrote:
Hello everyone,
v239 brought in portable services (a good description is at
http://0pointer.net/blog/walkthrough-for-portable-services.html) and while
I still cannot make it work (I do not have a /usr/lib/systemd/portablectl
despite having systemd --version reporting 239, but this is going to be a
separate question) I wanted to understand how to build a minimal portable
service.
A practical example could be dnsmasq. It is provided as a package and
depends (apt show dnsmasq) on netbase, dnsmasq-base, init-system-helpers
(>= 1.18~), lsb-base (>= 3.0-6). These packages may further depend on
something else.
It also brings in a set of files into the system:
root@srv ~# dpkg-query -L dnsmasq
/.
/etc
/etc/default
/etc/default/dnsmasq
/etc/dnsmasq.conf
/etc/dnsmasq.d
/etc/dnsmasq.d/README
/etc/init.d
/etc/init.d/dnsmasq
/etc/insserv.conf.d
/etc/insserv.conf.d/dnsmasq
/etc/resolvconf
/etc/resolvconf/update.d
/etc/resolvconf/update.d/dnsmasq
/lib
/lib/systemd
/lib/systemd/system
/lib/systemd/system/dnsmasq.service
/usr
/usr/lib
/usr/lib/resolvconf
/usr/lib/resolvconf/dpkg-event.d
/usr/lib/resolvconf/dpkg-event.d/dnsmasq
/usr/share
/usr/share/dnsmasq
/usr/share/dnsmasq/installed-marker
/usr/share/doc
/usr/share/doc/dnsmasq
Some of these are existing directories, some new ones and then there are
files (new, but possibly existing as well).
*How should I create a filesystem which has only the files required by the
packages (= the ones it brings in, as well as all the dependencies)?*
I know that I can dbootstrap a new system and install there dnsmasq - and
then hopefully use this as the tree to be attached via portablectl. This
however means that I do not have a "dnsmasq" portable service but rather a
"bionic install with dnsmasq installed on top". The main reason for me to
use portable service is to create small packages which encompass my
service, to be mounted on a more or less base core OS install (say, minimal
bionic). This would allow to get rid of several nspawn containers which do
exactly this (base OS + a package installed on top).
One of the ideas I had (but which seems very wrong) is to have a copy of
the core OS, then in another copy install the required packages, and then
make a diff of the two directories. But this looks horrible and is hardly
maintainable.
I would very much appreciate any pointers or hints on how to approach this.
Wojtek
_______________________________________________
systemd-devel mailing list
systemd-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
SMILE <http://www.smile.eu/>
20 rue des Jardins
92600 Asnières-sur-Seine
*Jérémy ROSEN*
Architecte technique
Responsable de l'expertise Smile-ECS
email jeremy.ro...@smile.fr <mailto:jeremy.ro...@smile.fr>
phone +33141402967
url http://www.smile.eu
Twitter <https://twitter.com/GroupeSmile> Facebook
<https://www.facebook.com/smileopensource> LinkedIn
<https://www.linkedin.com/company/smile> Github
<https://github.com/Smile-SA>
Découvrez l’univers Smile, rendez-vous sur smile.eu
<http://smile.eu/?utm_source=signature&utm_medium=email&utm_campaign=signature>
eco Pour la planète, n'imprimez ce mail que si c'est nécessaire
_______________________________________________
systemd-devel mailing list
systemd-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/systemd-devel
