.. _operational-impacts-9cf2e610b5b3:

===================
Operational Impacts
===================

The operational impact of Debian-based |prod| is small:

*  Functional equivalence with CentOS-based |prod|

*  Use of the |prod| CLIs and APIs will remain the same:

   *  |prod| on Debian will provide the same CLIs and APIs as |prod| on CentOS.

   *  |prod| on Debian will run on a 5.10 based kernel.

   *  |prod| on Debian will support the same set of Kubernetes APIs used in
      |prod| on CentOS.

   *  The procedure to install hosts will be unchanged by the migration from
      CentOS to Debian. Only the ``grub`` menu has been modified.

   *  The CLIs used for software updates (patching) will be unchanged by
      the migration from CentOS to Debian.

*  User applications running in containers on CentOS should run on Debian
   without modification. Re-validation of containers on Debian is encouraged to
   identify any exceptions.

*  A small subset of operating system-specific commands will differ. Some of
   these changes result from the switch in distributions while others are
   generic changes that have accumulated since the release of the CentOS
   distribution currently used. For example:


   *  The Debian installation requires new pxeboot grub menus. See
      :ref:`Technology Preview Installation <deb-grub-deltas>`.

   *  Some prompt strings will be slightly different (for example: ssh login,
      passwd command, and others).

   *  Many 3rd-party software packages are running a newer version in Debian
      and this may lead to minor changes in syntax, output, config files, and
      logs.

   *  The URL to expose keystone service does not have the version appended.

   *  On Debian, interface and static routes need to be handled using system-API
      (host-route-\*, host-if-\* and host-addr-\*).

      *  Do not edit configuration files in ``/etc/network/`` as they are
         regenerated from sysinv database after a system reboot. Any changes
         directly done there will be lost.

      *  The static routes configuration file is ``/etc/network/routes``

      *  Interface configuration files are located in
         ``/etc/network/interfaces.d/``

   *   Debian stores network information in ``/etc/network`` instead of
       ``/etc/sysconfig/network-scripts`` location used in CentOS. However, the
       |prod| ``system …`` commands are unchanged. |deb-update-iso|

   *   Patching on Debian is done using ostree commits rather than individual
       RPMs.

       You can see which packages are updated by ostree using the :command:`dpkg
       -l` instead of :command:`rpm -qa` used on CentOS.

   *   The patching CLI commands and Horizon interactions are the same as for
       CentOS.

       *   The supported patching CLI commands for |deb-eval-release| are:

           * ``sw-patch upload``
           * ``sw-patch upload-dir``
           * ``sw-patch apply``
           * ``sw-patch remove``
           * ``sw-patch delete``
           * ``sw-patch query``
           * ``sw-patch show``
           * ``sw-patch query-hosts``
           * ``sw-patch host-install``
           * ``sw-patch host-install-async``
           * ``sw-patch install-local``

       However, since Debian patches work with ostree commits rather than
       RPMs, the patch contents visible on Horizon and CLI are different.

       Running the ``sw-patch show <patch-ID>`` CLI command or selecting
       **Software Management** and the patch name in Horizon displays details
       about the contents of a Debian patch including:

       * The number of ostree commits in this patch.

       * The base commit on which the patch can be applied.

       * The commit IDs that are associated with this patch.

       **CLI**

       Sample ``sw-patch show <patch-ID>`` output:

       .. code-block:: none

          DEBIAN_RR:
          Release:        22.06
          Patch State:    Available
          Status:         DEV
          Unremovable:    N
          RR:             Y
          Summary:        Reboot Required Patch 0015
          Description:    Reboot Required Patch for resolving subcloud unlock issue
          Install Instructions:
                          Please ensure that there is 450MB minimum available space in the directory where the patch is going to be placed.
          Warnings:       This patch requires PATCH_0014 to be installed first.
          Contents:

          No. of commits: 2
          Base commit:    d0a0d5ad78746c86ab477fb5ccb98d7e813484a9cb1c0a780363233794655fdc
          Commit1:        a386e76d6430f7fd6693d40379cccc838445f4abd409f158b919c010da80cb83
          Commit2:        647dcef3f32d61b3d341fab905f5267c5614d804cae5d295693a6098db6e4e6d


       **Horizon**

       Sample **Software Management** > *patch name* output.

       .. figure:: figures/debian_patching_details_horizon.png
          :width: 600px