From: Christoph Lameter <chris@waterf.org>
Subject: dpkg: delayed configuration causes crashes and inaccessible systems
To: submit@bugs.debian.org
Message-Id: <E0xQiSm-0002ck-00@cyrix200.waterf.org>
Date: Wed, 29 Oct 1997 16:27:52 -0800

Package: dpkg
Version: 1.4.0.19
Severity: critical

This is an earlier post of me re delayed configuration on debian-devel:

I am maintaining a couple of systems that I can just reach via telnet.
Upgrading the system means that functionality is stopped in the unpacking
phase of dpkg and not enabled until the configuration phase. That might
take quite a while if a large number of packages is upgraded and can lead
to severe problems with an internet server.

If packages could be equipped with some sort of flag that would tell dpkg
that this critical package needs to be configured immediately then this
problem would be solved. Two variations come to my mind:

1. A package needs to be immediately configured after installation.
2. A package needs to be immediately configured if upgraded.

Packages using this flag should not have any user interaction in the
postinst script so that the upgrade process does not stop by dpkg invoking
the postinst script.

Typical candidates for such functionality are:

netbase         Shutting down netbase means disabling inetd,portmapper!
                No telnet access no ftp access during the dpkg session. If
                something goes wrong your system is dead. If you are
                across the country somewhere then good luck.

netstd          Will stop routed and NFS. Loosing routed will shut your
                server down after a few minutes because it wont be able
                to route packages to you anymore.

nis             Shutting down NIS will probably prevent anyone
                from connecting to your systems. Having NIS down
                for any extended amount of time is suicide for the
                system.

libreadline*    For the hamm upgrade having an unconfigured readline
                can make bash dysfunctional.

bash            Is critical to the system. Anything that would prevent
                from working for any time period must be avoided.

ldso            must work at all times.

libraries       It is unhealthy to have important libraries in a state
                where important system software is not able to run because
                it depends on those libraries.

Server daemons might use the flag to restart the daemons immediately after
an upgrade in order to minimize downtime. Upgrading an Internet Server
while it is running in full operation becomes a real possibility.

So far I have also upgraded my servers under full operation but I had to
do it piece by piece by running dpkg -i on single .debs.

The immediate configuration option might help the installation process to
be more robust and improve the overall reliability of the Debian
distribution.

-- System Information
Debian Release: 1.3
Kernel Version: Linux cyrix200 2.1.60 #20 Mon Oct 27 18:11:52 PST 1997 i486 unknown

Versions of the packages dpkg depends on:
libc6	Version: 2.0.5c-0.1
libg++272	Version: 2.7.2.8-0.1
ncurses3.4	Version: 1.9.9g-5