apt wants to downgrade packages with pin-priority less than 1000
alon at turnkeylinux.org
Sat Dec 27 19:14:56 GMT 2008
Firstly, let me introduce myself, I am one of the developers for TurnKey
Linux, an opensource project that develops a family of lightweight
installable Ubuntu based Live CD appliances optimized for various
Now, down to business...
apt will attempt to downgrade an installed package if the pin-priority
of the package is greater than 99.
apt will not downgrade when pin-priorty is 99 or below because the
already installed package automatically gets a priority of 100.
According to the apt_preferences manpage (mentioned several times), apt
will *never* downgrade a package unless the priority of an available
version exceeds 1000.
I came across this issue because our package repository has not yet been
updated with the latest package, but the latest package has been
installed on the system.
Although this shouldn't matter, apt seems to be breaking its own rules
(unless I am missing something...)
My testing system:
Ubuntu 8.04.1 (Hardy)
apt 0.7.9ubuntu17.1 for i386 compiled on Oct 27 2008 18:11:08
# dpkg -s drupal5 |grep Version
# cat /etc/apt/preferences
Pin: release o=turnkeylinux
Note: the pin-priority can be anything larger than 99 to reproduce this,
and the same situation happens with other packages.
# apt-cache policy drupal5
Package pin: 5.10-3
*** 5.12-2 999
500 http://archive.turnkeylinux.org hardy-security/universe Packages
500 http://archive.ubuntu.com hardy-security/universe Packages
# apt-get install drupal5
The following packages will be DOWNGRADED:
In other words, the installed version is 5.12-2 but apt wants to
downgrade to the eariler version 5.10-3.
Is this a bug in apt, a bug in the documentation, or am I
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