UCS 2.4 - Univention

11 Software maintenance
must be verified that the update continues despite disconnection from the network. The tools screen and
at can be used for this. GNU Screen has been installed automatically as standard since UCS 2.4.
The package maintenance policies can be used for the update, which allow an automatic release update.
This is described in Section 11.3.5.
The command univention-updater can be used to install UCS release updates directly on the con-
sole. This supports the following variants:
• The univention-updater cdrom command is used to update a system from an inserted update
DVD or an ISO image. This can only be done on repository servers. As standard, the command
mount /cdrom is used to try to mount the DVD. The parameter −−cdrom can be used to add an
alternative path. The parameter −−iso can be used to access an existing ISO image.
If the system possesses a local repository, this is updated firstly.
• The command univention-updater net is used to update a system via the online repository
or a local repository in the domain. The update server is set by the Univention Configuration Reg-
istry variable repository/online/server. In this case too if an existing local repository on the
system is updated firstly, the update will use the local repository.
• If a UCS release update has already been imported in the systems’s local repository,
univention-updater local can be executed. The update then uses the local repository.
The parameter −−updateto can be used in all named run applications to specify to which version a
system should be updated. Higher versions are then not installed even if they are available.
Prior to the installation of a release update, a link to the release notes is displayed and a minute is waited
in which the update can still be cancelled. This can be skipped via the −−ignore-releasenotes option
or by setting the Univention Configuration Registry variable update/warning/releasenotes to no.
If the update has been performed successfully, a check should be made for whether new or updated
join scripts need to be run. This is not normally required on the DC master and DC backup sys-
tem roles. The Univention Management Console module Domain join or the command line program
univention-run-join-scripts, which can be found in the /usr/share/univention-join di-
rectory, is used for checking and starting the join scripts (see Section 5.3.10).
Attention:
It should be noted, that components marked as critical can block an upgrade to the next minor or major
release. More information can be found in Section 11.3.3.
11.3 Package maintenance
Packages can be installed, updated or removed on all UCS systems apart from thin clients. The three
processes are grouped under the term package maintenance.
UCS systems access repository servers during package maintenance. Package maintenance can be per-
formed manually or automatically. In automatic package maintenance the UCS systems check indepen-
dently whether updated packages are available, new packages should be installed or installed packages
should be deleted. The package maintenance also installs available security updates. Corresponding
commands and tools can be used to perform these actions manually.
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