Novell LINUX ENTERPRISE SERVER 11 - DEPLOYMENT, Deployment Manual

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Using the installation summary filter you see an overview of the packages you have
scheduled for installation. It is convenient for double-checking if many packages are
pending for installation.
9.2.2 Checking Software Dependencies
The software of one package might only work properly if the required package is also
installed. If packages with identical or similar functionality use the same system resource,
they should not be installed at the same time, because this would cause a package con-
flict.
When the package manager starts, it examines the system and displays the installed
packages. When you select to install and remove packages, the package manager auto-
matically checks the dependencies and selects any other required packages (resolution
of dependencies). If you select or deselect conflicting packages, the package manager
indicates this and suggests possible solutions to this problem (resolution of conflicts).
Check Dependencies and Autocheck are located under the information window. If you
click Check Dependencies, the package manager checks if the current package selection
results in any unresolved package dependencies or conflicts. In the event of unresolved
dependencies, the required additional packages are selected automatically. For package
conflicts, the package manager opens a dialog that shows the conflict and offers various
options for solving the problem.
If you activate Autocheck, any change of a package status triggers an automatic check.
This is a useful feature, because the consistency of the package selection is monitored
permanently. However, this process consumes resources and can slow down the package
manager. For this reason, Autocheck is not activated by default. In either case, a consis-
tency check is performed when you confirm your selection with Accept.
For example,
sendmail
and
postfix
may not be installed concurrently. Figure 9.1,
“Conflict Management of the Package Manager” (page 146) shows the conflict message
prompting you to take a decision.
postfix
is already installed. Accordingly, you can
refrain from installing
sendmail
, remove
postfix
, or take the risk and ignore the
conflict.
Installing or Removing Software 145