How to remove systemd from a Debian Stretch installation

Using sysvinit instead of systemd in Debian Stretch

Required steps

1. Install the sysvinit packages: apt-get install sysvinit-core
2. Copy inittab: cp /usr/share/sysvinit/inittab /etc/inittab
3. Reboot the system: reboot

Optional steps

1. Install udisks2 and/or policykit if needed for graphical desktops or build them from Debian sources by applying a small patch.
2. Remove the systemd packages, including libpam-systemd: apt-get remove --purge --auto-remove systemd
3. Prevent apt from installing systemd-related packages in the future: echo -e 'Package: *systemd*\nPin: release *\nPin-Priority: -1\n' > /etc/apt/preferences.d/systemd

Using sysvinit instead of systemd in Debian Stretch (variant)

Required steps

1. Configure the nosystemd repo: echo -e 'deb nosystemd-stretch main' > /etc/apt/sources.list.d/nosystemd.list
2. Configure the nosystemd apt preference: Note: libsystemd0 does not need to be removed as it is harmless without systemd itself.
   echo -e 'Package: *\nPin: origin nPin-Priority: 1100\n' > /etc/apt/preferences.d/nosystemd
echo -e 'Package: libsystemd0\nPin: version *\nPin-Priority: 500\n' >> /etc/apt/preferences.d/nosystemd
echo -e 'Package: *systemd*\nPin: release *\nPin-Priority: -1\n' >> /etc/apt/preferences.d/nosystemd
   
3. Get the GPG key for the repo: wget -qO - | apt-key add -
   -OR-
   apt-get install kilobyte-archive-keyring
   
4. Install the sysvinit packages: apt-get install sysvinit-core sysvinit-utils
5. Copy inittab: cp /usr/share/sysvinit/inittab /etc/inittab
6. Reboot the system: reboot

Optional steps

1. Remove the systemd packages, including libpam-systemd: apt-get purge systemd*
   
2. For graphical desktops, systemd independent udisks2 and/or policykit will be pulled from the repo above.
   
   
   

Support status

A January 2017 bug report discussion and a February 2017 mailing list thread indicate that Debian developers are continuing to support sysvinit.