Re: documenting on how not starting a daemon upon installation

[Marvin Renich <mrvn@renich.org>]

Thanks, Russ, Ansgar, and Marco for the explanations.

So in summary:

* For systems running systemd

  - systemctl mask works well to disable individual daemons until
    explicitly re-enabled, regardless of which mechanism the package
    uses (systemd service or init script) to start the daemon.

  - systemctl mask requires you to know, prior to installing a package,
    the names of all services the package installs.
  - it has not been mentioned whether systemd provides any facility to
    block starting _all_ services for a period of time (esp when working
    in a chroot), including services that have not been installed at the
    time the hypothetical "block all services" command is invoked.

* For systems running either systemd or sysvinit (maybe also runit?)

  - policy-rc.d can block individual systemd services and init scripts.
  - policy-rc.d can block all services and init scripts.

  - policy-rc.d is not well documented.
  - policy-rc.d requires manually writing a shell script (a trivial
    one-liner for the "block all" case).

It is also worth noting that systemctl mask works on any systemd
distribution, not just Debian GNU/Linux, but not other Debian ports with
non-Linux kernels.

And, policy-rc.d presumably works on any Debian distribution, not just
Debian GNU/Linux, but not on non-Debian distributions.

It looks to me like policy-rc.d is the best fit for performing package
installations in a chroot (the OP's original question, IIUC), while
systemctl mask is the right choice for manually dealing with maintenance
of individual, already installed packages.

...Marvin