Drop CentOS Linux 8 image builds

(cherry picked from commit 405fca90f2c8d3763ac56ce8b925611d136bba6c)

Change-Id: I95ea4a66a80bf035f8bd1180790c7e0c85d759ed
(cherry picked from commit 07f519996381789c1f21850cfc9b27f3b86a6f4c)

4 files changed, 12 insertions, 49 deletions

diff --git a/.zuul.d/centos.yaml b/.zuul.d/centos.yaml
index 3d9f956cf..0096d2ca2 100644
--- a/.zuul.d/centos.yaml
+++ b/.zuul.d/centos.yaml
@@ -4,8 +4,6 @@
       jobs:
         - kolla-build-centos-binary
         - kolla-build-centos-source
-        - kolla-build-centos8-binary
-        - kolla-build-centos8-source
         - kolla-ansible-centos-source
         - kolla-ansible-centos-binary
         - tripleo-build-containers-centos-7:
@@ -20,7 +18,6 @@
       queue: kolla
       jobs:
         - kolla-build-centos-source
-        - kolla-build-centos8-source
         - kolla-ansible-centos-source
         - tripleo-build-containers-centos-7:
             voting: true
@@ -34,14 +31,10 @@
       jobs:
         - kolla-publish-centos-source
         - kolla-publish-centos-binary
-        - kolla-publish-centos8-source
-        - kolla-publish-centos8-binary
     release:
       jobs:
         - kolla-publish-centos-source
         - kolla-publish-centos-binary
-        - kolla-publish-centos8-source
-        - kolla-publish-centos8-binary
     experimental:
       jobs:
         - kolla-ansible-bifrost-centos-source:
@@ -67,12 +60,6 @@
       install_type: binary
 
 - job:
-    name: kolla-build-centos8-binary
-    parent: kolla-build-centos-binary
-    vars:
-      base_tag: 8
-
-- job:
     name: kolla-publish-centos-binary
     parent: kolla-build-centos-binary
     post-run: tests/playbooks/publish.yml
@@ -82,12 +69,6 @@
       - kolla_dockerhub_creds
 
 - job:
-    name: kolla-publish-centos8-binary
-    parent: kolla-publish-centos-binary
-    vars:
-      base_tag: 8
-
-- job:
     name: kolla-build-centos-source
     parent: kolla-base
     nodeset: kolla-centos
@@ -97,12 +78,6 @@
       install_type: source
 
 - job:
-    name: kolla-build-centos8-source
-    parent: kolla-build-centos-source
-    vars:
-      base_tag: 8
-
-- job:
     name: kolla-publish-centos-source
     parent: kolla-build-centos-source
     post-run: tests/playbooks/publish.yml
@@ -110,9 +85,3 @@
       publisher: true
     secrets:
       - kolla_dockerhub_creds
-
-- job:
-    name: kolla-publish-centos8-source
-    parent: kolla-publish-centos-source
-    vars:
-      base_tag: 8
diff --git a/doc/source/admin/image-building.rst b/doc/source/admin/image-building.rst
index ead62e9af..6d585ba03 100644
--- a/doc/source/admin/image-building.rst
+++ b/doc/source/admin/image-building.rst
@@ -78,21 +78,6 @@ See the :ref:`support matrix <support-matrix-base-images>` for information on
 supported base image distribution versions and supported images on each
 distribution.
 
-The Train ``9.1.0`` release supports both CentOS 7 and 8 base container images.
-The default is to use CentOS 7. CentOS 8 may be used as follows:
-
-.. code-block:: console
-
-   kolla-build --base centos --base-tag 8
-
-Kolla uses the tag to set defaults for the distribution Python version and
-package manager. If you need to use a base image with a different tag, use the
-following options:
-
-.. code-block:: console
-
-   kolla-build --base centos --base-image <base image> --base-tag <base tag> --distro-package-manager dnf --distro-python-version 3.6
-
 It is possible to build only a subset of images by specifying them on the
 command line:
 
diff --git a/doc/source/support_matrix.rst b/doc/source/support_matrix.rst
index 4aa9e8df1..a44608340 100644
--- a/doc/source/support_matrix.rst
+++ b/doc/source/support_matrix.rst
@@ -17,14 +17,17 @@ The following base container images are supported:
 .. note::
 
    Train is the last release of Kolla to support CentOS 7 as a base container
-   image. The Train ``9.1.0`` release also supports CentOS 8 images, and
-   provides a route for migration.
+   image.
+
+.. note::
+
+   CentOS 8 is no longer supported since it has been marked as End of Life
+   and repositories have been removed from CentOS mirrors.
 
 ============= ============ ================
 Distribution  Default base Default base tag
 ============= ============ ================
 CentOS 7      centos       7
-CentOS 8      centos       8
 Debian Buster debian       10
 RHEL 8        rhel         8
 Ubuntu Bionic ubuntu       18.04
diff --git a/releasenotes/notes/centos-8-eol-4500333b5e01f448.yaml b/releasenotes/notes/centos-8-eol-4500333b5e01f448.yaml
new file mode 100644
index 000000000..a22d0e579
--- /dev/null
+++ b/releasenotes/notes/centos-8-eol-4500333b5e01f448.yaml
@@ -0,0 +1,6 @@
+---
+critical:
+  - |
+    CentOS Linux 8 (non-Stream) support has been dropped, since
+    repositories have been removed from CentOS mirrors  - see
+    `announcement <https://www.centos.org/centos-linux-eol/>`_.