Re: How to consistently install a set of packages?

[Kailash <listskailash@gmail.com>]

On Thu, 6 Jun 2013 17:30:24 +1000
David <bouncingcats@gmail.com> wrote:

> On 06/06/2013, James Richardson <james@jamestechnotes.com> wrote:
> > David wrote:
> 
> [...]
> 
> >> Because some packages create users and groups, I want to be sure
> >> that these packages are installed in the same sequence on every PC
> >> so that numeric uid & gid in /etc/passwd and /etc/group end up the
> >> same on all PCs. This will make admin easier when keeping the
> >> shared data in sync if the numeric uid and gid are the same in
> >> every OS.
> 
> > The only thing I can suggest (and I am by no means an expert), is to
> > create the users/groups before installing the packages. You can use
> > dpkg --get/--set-selections to set the selection state of the
> > packages, but as this doesn't actually install anything, I would
> > doubt it would give apt-get/aptitude any hints about ordering, but
> > if the user/groups existed before hand it should still be ok.
> 
> Hi James
> 
> Thank you for your thoughts. I appreciate your lateral thinking which
> is appealing. But I wonder how a package install process would make
> the decision to take over a pre-existing user or group?
> 
> For example, if I created user=approx and then installed the approx
> package which wants to run as user=approx, how thoroughly would its
> installer script assess if the pre-existing user=approx is free for
> its use? If there already was some other unrelated user=approx, it
> would be undesirable for the approx package to assimilate that user.
> 
> And would each package that wants to do similar behave consistently?
> 
> Any thoughts on that?
> 
> My guess would be that a package install would probably abort if the
> user or group it wanted was already in use. Or perhaps the installer
> will ask what to do? I'd prefer if it would run unattended. I can't
> set up a test immediately, but if necessary I can test this later in
> the week.
> 
> 

Hi,

I did some searching re UIDs and GIDs, and it appears that the
adduser.conf file can be used to manage this behavior. 

In addition if you look at the manpage of adduser the option "--uid"
will allow you to choose the user's ID. And addgroup has a similar
option. 

So, perhaps all you need is a common script that does it for you.
Please do refer to the policy manual re the allocation policy for
Debian.
http://www.debian.org/doc/debian-policy/ch-opersys.html#s9.2

HTH,
K.