On Tue, 20.07.10 20:24, Toshio Kuratomi (a.badger(a)gmail.com) wrote:
> On Wed, Jul 14, 2010 at 2:50 PM, Adam Williamson <awilliam(a)redhat.com> wrote:
> > On Wed, 2010-07-14 at 15:42 -0600, Kevin Fenzi wrote:
> >
> >> Perhaps someone could put together a wiki page for lazy sysadmins with
> >> a Q&A? ie, I used to do this in upstart/sysvinit, how do I do it with
> >> systemd?
> >
> > Jóhann Guðmundsson (viking_ice) has been working on something along
> > these lines:
> >
> >
http://fedoraproject.org/wiki/User:Johannbg/QA/Systemd
> >
> > it was mentioned in the QA meeting a few weeks back.
>
> I have a few requests for things to add to that page :-)
>
> * What replaces chkconfig
> * What replaces /etc/init.d/SERVICENAME start | stop ?
>
> Similarly, for packaging guidelines updates, how do we install
> packages that provide services and have them not start up?
The longer answers for most of these questions you find in Jóhann's
reply. But a few additional notes:
- If you only install a SysV init script, then continue to use chkconfig
as usual. It works as intended to enable/disable SysV init
scripts. Only if you use native systemd unit files you should use
systemd-install instead. Note that most operations systemd-install
executes are very easy however, as all it does is creating/removing a
few suggested symlinks which are listed in a [Install] section in
the unit file. It is OK and even expected to manually create
additional symlinks, or remove symlinks, as the administrator likes.
- Regardless whether systemd or SysV init scripts/unit files are used,
"systemctl start" and "systemctl stop" are the recommended
replacements for "service foo start" and "service foo stop".
Howver,
as soon as
https://bugzilla.redhat.com/show_bug.cgi?id=612728 is fixed
you can use the old syntax for SysV scripts too in which case the
right thing happens, but you'll get a blurb printed that suggests you
to use "systemctl" instead, the next time.
- If you want to enable and possibly start a service from the %post of
an RPM then use the "systemd-install enable" command, which will
create a few symlinks as listed in the [Install] section of the unit
file. On top of that you may also pass --realize=... to the command,
which allows you to not only enable the unit for the next boot, but
also have the changes take effect immediately: i.e. --realize=reload
is the very least you should use, which simply makes systemd aware of
the changed symlinks. Then, at time of %preun you should use
--realize=yes which makes sure the daemon is stopped in
deinstallation. For a few daemons it makes sense to restart them if
they are running already during upgrade. Use --realize=minimal for
those. For even others (usually very low-level ones) it might even
make sense to start them right-away after installation, even if they
were not running before. For those use --realize=maybe. But which
option you use really depends on the package. Most packages
should probably stick to --realize=yes on %preun and --realize=reload
in %post. Suggested .spec file fragments you find in the daemon(7) man
page.
Normally, we don't want a service to be started just because the package has
been installed:
.
This is the current recommended scriptlets:
%post
# This adds the proper /etc/rc*.d links for the script
/sbin/chkconfig --add <script>
%preun
if [ $1 = 0 ] ; then
/sbin/service <script> stop >/dev/null 2>&1
/sbin/chkconfig --del <script>
fi
%postun
if [ "$1" -ge "1" ] ; then
/sbin/service <script> condrestart >/dev/null 2>&1 || :
fi
I think I've got the %preun translated correctly but I'm not sure about
either the %post or %postun::
%post
# Don't need a %post as systemd automatically knows about the defaults?
%preun
if [ $1 = 0 ] ; then
/usr/bin/systemd-install disable %{unit name}.service --realize=disable > /dev/null
2>&1 || :
fi
%postun
if [ "$1" -ge "1" ] ; then
# Can't figure out how to do a conditional restart here. Help?
fi
-Toshio