source/upgrading/upgrade/_java_version.rst

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.. sub-section included in upgrade notes.

Java Version Requirement
------------------------

CloudStack |version| requires installation of Java 11 JRE for management server
and the KVM agent. On installing or upgrading cloudstack-management and/or
cloudstack-agent packages, please configure Java 11 as the default java
version using:

   .. parsed-literal::

      $ sudo alternatives --config java

Note: For Ubuntu distributions where the openjdk-11 packages are not available
from the main repositories, the JRE can be installed from an external PPA such
as openjdk-r. The PPA can be added before installation/upgrade:

   .. parsed-literal::

      $ sudo add-apt-repository ppa:openjdk-r/ppa
      $ sudo apt-get update