On 24/02/15 00:32, Nuno Magalhães wrote:
> On wheezy i don't see nginx-extras depending on udev or any systemd*.
> I don't have jessie but i couldn't trace any dependencies on
> packages.debian.org either. Where did you see these dependencies? Can
> you apt-rdepend them? The closest i could find was nginx-extras »
> nginx-common » init-system-helpers but it goes on to perl-base » dpkg
> » libselinux1 » libpcre3 and that's it. Maybe i missed something in
> libselinux1? Could you be using a third-party module that may have
> other dependencies? I didn't check Recommends.

Yes, I need some of the nginx's third-party modules especially
HttpHeadersMore module. That is why I chose nginx-extras. I had some
issues on my VPS using nginx that I dpkg-buildpackage myself. I forgot
the detail of the issues as it was about 7 years ago. Since then I
decided to stay with what ever version of nginx-extras on testing
repository.

Did you mean to check the dependencies of nginx-extras to other packages
using "apt-cache depends"? If so here is the output.

# apt-cache depends nginx-extras
nginx-extras
   Depends: nginx-common
   Depends: perl
   Depends: <perlapi-5.20.1>
     perl-base
   Depends: libc6
   Depends: libexpat1
   Depends: libgd3
   Depends: libgeoip1
   Depends: libluajit-5.1-2
   Depends: libpam0g
   Depends: libpcre3
   Depends: libperl5.20
   Depends: libssl1.0.0
   Depends: libxml2
   Depends: libxslt1.1
   Depends: zlib1g
   Suggests: nginx-doc
   Conflicts: nginx-full
   Conflicts: nginx-light
   Breaks: nginx

It does not explicitly show the dependencies to the packages that depend
on any systemd related packages. But I remember that I can not install
nginx-extras after I cleaned up my VPS as much as possible from using
systemd related packages. Unfortunately, I didn't take a note of what
made it fails to install.

Your comment about "Recommends" makes me think that I didn't properly do
the clean up. I think I will re-do that, but start from Debian squeeze.
I will log my SSH window this time, as I don't want to re-do this.

Here is what I plan to do:

1. Re-install Xen DomU image of Debian squeeze

2. Add the following files:

    # cat /etc/apt/preferences.d/blocksystemd
    Package: *systemd*
    Pin: origin ""
    Pin-Priority: -1
    #
    # cat /etc/apt/apt.conf.d/77norecommends
    APT::Install-Recommends "0";
    APT::Install-Suggests "0";

3. Keep switching the repository from squeeze --> wheezy --> jessie -->
testing, and do dist-upgrade on each step

4. I will pin some of the packages to their previous version when they
fail to be upgraded

Due to the pinning, I might not get the latest version of packages from
testing repositories. But I think I can live with that until Devuan is
being released.

Is there anything that I need to add in order to really avoid using
anything related to systemd? Or perhaps, something that I need to do
which could provide more information on the dependencies on systemd and
its related packages, in case that would be needed for Devuan development?