Unattended upgrades

This script can upgrade packages automatically and unattended.
However, it is not enabled by default. Most users enable it via the Software Sources program (available in System/Administration).

If you would prefer to enable it from the command line, run "sudo dpkg-reconfigure -plow unattended-upgrades".

It will not install packages that require dependencies that can't be fetched from allowed origins and it will check for conffile prompts before the install and holds back any package that requires them.

Setup

The unattended-upgrades package is normally activated by software-properties or via debconf. By default this runs an update every day.

The main way to specify which packages will be auto-upgraded is by means of their "origin" and "archive". These are taken respectively from the Origin and Suite fields of the repository's Release file, or can be found in the output of:

$ apt-cache policy

in the "o" and "a" fields for the given repository.

The default setup auto-updates packages in the main and security archives, which means that only stable and security updates are applied.

This can be changed either with the "Unattended-Upgrade::Allowed-Origins" or the "Unattended-Upgrade::Origins-Pattern" apt configuration lists, which can be configured in /etc/apt/apt.conf.d/50unattended-upgrades. Also in this file are a range of other options that can be configured.

Allowed-Origins is a simple list of patterns of the form "origin:archive".

Origins-Pattern allows you to give a list of (glob-style) patterns to match against. For example:

 Unattended-Upgrade::Origins-Pattern {
        "origin=Google\, Inc.,suite=contrib";
        "site=www.example.com,component=main";
 };

will upgrade a package if either the origin is "Google, Inc." and suite is "contrib" or if it comes from www.example.com and is in component "main". The apt-cache policy short identifiers (e.g. "o" for "origin") are also supported.

If you already configure what to install via apt pinning, you can simply use "origin=*", e.g.:

 Unattended-Upgrade::Origins-Pattern {
        "origin=*";
 };

All operations are be logged in /var/log/unattended-upgrades/. This includes the dpkg output as well. The file /etc/logrotate.d/unattended-upgrades controls how long logfiles are kept and how often they are rotated. See the logrotate manpage for details.

If you want mail support you need to have a mail-transport-agent (e.g postfix) or mailx installed.

Debugging

If something goes wrong or if you want to report a bug about the way the script works its a good idea to run:

$ sudo unattended-upgrade --debug --dry-run

and look at the resulting logfile in: /var/log/unattended-upgrades/unattended-upgrades.log then. It will contain additional debug information.

Manual Setup

To activate this script manually you need to ensure that the apt configuration contains the following lines (this can be done via the graphical "Software Source" program or via dpkg-reconfigure as well):

APT::Periodic::Update-Package-Lists "1";
APT::Periodic::Unattended-Upgrade "1";

This means that it will check for upates every day and install them (if that is possible). If you have update-notifier installed, it will setup /etc/apt/apt.conf.d/10periodic. Just edit this file then to fit your needs. If you do not have this file, just create it or create/edit /etc/apt/apt.conf - you can check your configuration by running "apt-config dump".

Supported Options Reference

• Unattended-Upgrade::Allowed-Origins - list of (origin:archive) pairs

Only packages from this origin:archive pair will be installed. You can see all available origin:archive pairs by running apt-cache policy and checking the "o=" and "a=" fields. Variable substitution is supported for ${distro_id} that contains the output of lsb_release -i and ${distro_codename} that contains the output of lsb_release -c.

Example:

Unattended-Upgrade::Allowed-Origins {
   "${distro_id}:${distro_codename}-security";

• Unattended-Upgrade::Package-Blacklist - list of regular expressions

No packages that match the regular expressions in this list will be marked for upgrade. If a package A has a blacklisted package B as a dependency then both packages A and B will not be upgraded. Note that its a list of regular expressions so you may need to escape special charackters like "+" as "+".

Example:

Unattended-Upgrade::Package-Blacklist {
    "libstdc\+\+6";
};

• Unattended-Upgrade::Package-Whitelist - list of regular expressions

Only packages that match the regular expressions in this list will be marked for upgrade. By default dependencies of whitelisted packages are allowed. This can be changed to allow only ever allow whitelisted packages with the Unattended-Upgrade::Package-Whitelist-Strict boolean option.

Example:

Unattended-Upgrade::Package-Whitelist {
    "bash";
};

• Unattended-Upgrade::Package-Whitelist-Strict - boolean (default:False)

When set, allow only packages in Unattended-Upgrade::Package-Whitelist to be upgraded. This means that you also need to list all dependencies of a whitelisted packages, e.g. if A depends on B and only A is whitelisted, it will be held back.

Example:

Unattended-Upgrade::Package-Whitelist-Strict "true";

• Unattended-Upgrade::AutoFixInterruptedDpkg - boolean (default:True)

Run dpkg --force-confold --configure -a if a unclean dpkg state is detected. This defaults to true to ensure that updates get installed even when the system got interrupted during a previous run.

• Unattended-Upgrade::MinimalSteps - boolean (default:False)

Optimize for safety against e.g. power failure by performing the upgrade in minimal self-contained chunks. This also allows sending a SIGINT to unattended-upgrades and it will stop the upgrade when it finishes the current upgrade step.

• Unattended-Upgrade::InstallOnShutdown - boolean (default:False)

Perform the upgrade when the machine is shutting down instead of doing it in he background while the machine is running.

• Unattended-Upgrade::Mail - string (default:"")

Send an email to this address with information about the packages upgraded. If empty or unset no email is send. This option requires a working local mail setup.

Example:

Unattended-Upgrade::Mail "user@example.com";

• Unattended-Upgrade::MailOnlyOnError - boolean (default:False)

Only generate a email if some problem occured during the unattended-upgrades run.

• Unattended-Upgrade::Remove-Unused-Dependencies - boolean (default:False)

Remove all unused dependencies after the upgrade finished.

• Unattended-Upgrade::Automatic-Reboot - boolean (default:False)

Automatically reboot WITHOUT CONFIRMATION if the file /var/run/reboot-required is found after the upgrade

• Unattended-Upgrade::Automatic-Reboot-WithUsers - boolean (default:True)

Automatically reboot even if users are logged in.

• Unattended-Upgrade::Keep-Debs-After-Install - boolean (default:False)

Keep the downloaded deb packages after successful installs. By default those are removed after successful installs.

• Acquire::http::Dl-Limit - integer (default:0)

Use apt bandwidth limit feature when fetching the upgrades. The number is how many kb/sec apt is allowed to use

Example - limit the download to 70kb/sec:

Acquire::http::Dl-Limit "70";