We want to stop systemd from being added to docker images, because of rpm requiring systemctl.

[Lennart Poettering]

On Tue, 29.04.14 16:58, Alexander Larsson (alexl at redhat.com) wrote:

> On tis, 2014-04-29 at 12:33 +0200, Lennart Poettering wrote:
> > On Mon, 28.04.14 17:01, Daniel J Walsh (dwalsh at redhat.com) wrote:
> > 
> > > The problem  is lots of services require systemd because they ship a
> > > unit file and want systemctl reload to happen.  Systemd then triggers a
> > > require for udev and kmod, which docker containers do not need.
> > 
> > If you discount the docs/man pages of the RPMs, how much does kmod,
> > udev, systemd actually contribtue in bytes to your docker images?
> 
> Its around 15 megs or so, although on rhel7 its 20 megs larger because
> of a dependency that kmod has on /usr/bin/nm (binutils) that doesn't
> seem to be there on fedora kmod. This seems like a bug in fedora though,
> as kmod ships /usr/sbin/weak-modules which calls nm, so once fixed
> fedora would be at 35 meg too.

I am pretty sure that the weak-modules thing should just go. It's
outdated cruft, for some enterprise thing, and inused in Fedora. I'd
really recommend to just drop it from the Fedora package...

> But, even if the size is small that is not the full picture. There are a
> bunch of dependencies like dbus (the daemon), device-mapper, kmod, and
> iptables that are recursively pulled in by systemd that don't really

device-mapper? iptables? That sounds wrong... Any idea how that gets
pulled in? the dm libs might get pulled in indirectly via libcryptsetup,
but the other dm tools really shouldn't be. And iptables i really don't
see how that's pulled in?

dbus (the daemon) is probably something we can turn around to not
require. I mean, it's needed during runtime if you boot a full OS
container or host, but I figure we don#t really have to pull this in
like this...

Lennart

-- 
Lennart Poettering, Red Hat