Bug#743274: insserv: warns about configuration changes

[Jesse Smith]

This is an interesting issue. I think this is what is happening:

1. update-rc.d wants to disable the osspd service. To do this is creates
a file called /etc/init/osspd.override.

2. update-rc.d then calls insserv. insserv sees that the osspd script
normally starts in runlevels "2 3 4 & 5", but there is an override in
place preventing the script from starting.

3. insserv then warns about the situation, to let the user know osspd's
default runlevels have been altered.

What makes this tricky, in my mind, is that if insserv were run as a
stand-alone program from the command line, it would be entirely correct
to warn the user that a script's defaults were overridden and its
behaviour changed. If I were to simply run "insserv" on its own, this is
what I would want.

But in this case the update-rc.d script is calling insserv, insserv
isn't being run stand-alone. Since we just told update-rc.d to disable
osspd, and we want that override behaviour, the warning seems entirely
out of place.

In other words, I believe both update-rc.d and insserv are behaving
correctly, and this would be proper behaviour if insserv were run on its
own. The problem is mixing the two together.

I have two suggestions to improve the current behaviour:

1. update-rc.d can be edited to catch the warning. Piping output from
insserv and running it through sed or grep would avoid warnings about
scripts update-rc.d had just changed.

2. We can add a quiet/silent flag (maybe -q) to insserv. When that flag
is present, the program does not print out warnings. We would still
print serious errors, but not minor warnings for override situations.
Then the update-rc.d script can just call "insserv -q" to avoid extra
output like this.


I'm open to feedback but I think #2 is probably the best way forward for
everyone. Thoughts?

- Jesse