ezyang’s blog

unattended-upgrades is a nifty little package that will go ahead and automatically install updates for you as they become enabled. No serious system administrator should use this (you are testing updates before pushing them to the servers, right?) but for many personal uses automatic updates are really what you want; if you run sudo aptitude full-upgrade and don't read the changelog, you might as well turn on unattended upgrades. You can do this by adding the line APT::Periodic::Unattended-Upgrade "1" to /etc/apt/apt.conf.d/10periodic (thanks Ken!)

Of course, the default configuration they give you in /etc/apt/apt.conf.d/50unattended-upgrades only pulls updates from their security repository, and they only give you a commented out line for normal updates. People have asked, "well, how do I pull automatic updates from other repositories?" Maybe you have installed Chromium dailies; seeing the "you have updates" icon every day can be kind of tiresome.

Well, here's how you do it:

1. Find out what URL the PPA you're interested in points to. You can dig this up by looking at /etc/apt/sources.list or /etc/apt/sources.list.d/ (the former is if you manually added a PPA at some point; the latter is likely if you used add-apt-repository).
2. Navigate to that URL in your browser. Navigate to dists, and then navigate to the name of the distribution you're running (for me, it was karmic). Finally, click Release. (For those who want to just enter the whole URL, it's http://example.com/apt/dists/karmic/Release).
3. You will see a number of fields Fieldname: Value. Find the field Origin and the field Suite. The two values are the ones to put in Allowed-Origins.

For example, the Ksplice repository has the following Release file:

Origin: Ksplice
Label: Ksplice
Suite: karmic
Codename: karmic
Version: 9.10
Date: Sun, 07 Feb 2010 20:51:12 +0000
Architectures: amd64 i386
Components: ksplice
Description: Ksplice packages for Ubuntu 9.10 karmic

This translates into the following configuration:

Unattended-Upgrade::Allowed-Origins {
       "Ksplice karmic";
};

And that's it! Go forth and make your systems more secure through more timely updates.

Bonus tip. You can turn on unattended kernel updates via Ksplice by editing /etc/uptrack/uptrack.conf and setting autoinstall = yes.