Chapter 2. General Updates

In-place upgrade from Red Hat Enterprise Linux 6 to Red Hat Enterprise Linux 7

An in-place upgrade offers a way of upgrading a system to a new major release of Red Hat Enterprise Linux by replacing the existing operating system. To perform an in-place upgrade, use the Preupgrade Assistant, a utility that checks the system for upgrade issues before running the actual upgrade, and that also provides additional scripts for the Red Hat Upgrade Tool. When you have solved all the problems reported by the Preupgrade Assistant, use the Red Hat Upgrade Tool to upgrade the system.
For details regarding procedures and supported scenarios, see the Migration Planning Guide and the solution document dedicated to the upgrade.
Note that the Preupgrade Assistant and the Red Hat Upgrade Tool are available in the Extras channel.

preupgrade-assistant rebased to version 2.3.3

The preupgrade-assistant packages have been upgraded to version 2.3.3, which provides a number of bug fixes, enhancements, and other changes over the previous version. Notably:
  • A new preupg-diff tool has been added, which compares multiple Preupgrade Assistant XML reports: one new with unidentified problems and other reports with already analyzed problems. The tool helps to find issues that emerged in the new report by filtering out results that are the same in the new report and in at least one of the analyzed XML files. The output of the trimmed report is available in the XML and HTML format.
  • Two new return codes have been added: 29 for internal error, and 30 for user abort.
  • The meaning of the return code 22 has been changed to invalid CLI option.
  • The STDOUT and STDERR output in the assessment report of the Preupgrade Assistant have been separated into two fields: Additional output for STDOUT and Logs for STDERR.
  • The python module to be imported by the Preupgrade Assistant modules written in Python has been renamed from preup to preupg. Additionally, the preup_ui_manage executable has been renamed to preupg-ui-manage.
  • The exit_unknown function and the $RESULT_UNKNOWN variable have been removed. Instead of the unknown result, set the error result by using the exit_error function.
  • The set_component module API function has been removed.
  • The component input parameter has been removed from the following module API functions: log_error, log_warning, log_info, and log_debug. (BZ#1427713, BZ#1418697, BZ#1392901, BZ#1393080, BZ#1372100, BZ#1372871)

Preupgrade Assistant enables blacklisting to improve performance

Preupgrade Assistant now supports creation of a blacklist file, which enables to skip all executable files on a path with a listed prefix. Users can activate this functionality in the /etc/preupgrade-assistant.conf file by setting the exclude_file value to the blacklist file name in the xccdf_preupg_rule_system_BinariesRebuild_check section. For example:
[xccdf_preupg_rule_system_BinariesRebuild_check]
exclude_file=/etc/pa_blacklist
Each line of the blacklist file contains a path prefix of executable files to be excluded. Previously, significant performance problems occured when a large partition was mounted and the RHEL6_7/system/BinariesRebuild module checked numerous files on a list of executables. Now, users can filter out unimportant executable files and thus reduce time the module consumes. Note that this feature is expected to be changed in the future. (BZ#1392018)

Key file names unified in Preupgrade Assistant modules

Previously, each module in Preupgrade Assistant used different file names for certain required files, which made testing and orientation complicated. With this update, the key file names have been unified to module.ini (the metadata INI file), check (the check script), and solution.txt (a solution text) in each of the modules. Additionaly, multiple rules (module IDs) have been renamed to conform with this change, so each rule now contains the unified _check suffix, for example, in the result.html and result.xml files. (BZ#1402478)

A new RHDS module to check a possibility of an in-place upgrade of an RHDS system

This update introduces a new Red Hat Directory Server (RHDS) module, which checks for relevant installed RHDS packages and gives users information about the possibility of an in-place upgrade of the RHDS system. As a result, if the relevant packages are installed, and the basic directory instance has been configured, the module creates a backup of the configuration files and prints information about them. (BZ#1406464)

cloud-init moved to the Base channel

As of Red Hat Enterprise Linux 6.9, the cloud-init package and its dependencies have been moved from the Red Hat Common channel to the Base channel. Cloud-init is a tool that handles early initialization of a system using metadata provided by the environment. It is typically used to configure servers booting in a cloud environment, such as OpenStack or Amazon Web Services. Note that the cloud-init package has not been updated since the latest version provided through the Red Hat Common channel. (BZ#1421281)