Merge pull request #57195 from marcoceppi/s390x-fixes

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Use an s390x default-http-backend

This needs to be refactored to eventually say all non x86 architectures place a -arch() in the image name to support ppc64el, arm, etc.

Most all gcr.io/google_containers have -arch() image names.


**What this PR does / why we need it**:

Adds s390x images for when deploying to z system mainframes for default-http-backend image

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes https://github.com/juju-solutions/bundle-canonical-kubernetes/issues/455

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

cluster/juju/layers/kubernetes-worker/reactive/kubernetes_worker.py

@@ -634,6 +634,12 @@ def launch_default_ingress_controller():
     context['arch'] = arch()
     addon_path = '/root/cdk/addons/{}'
 
+    context['defaultbackend_image'] = \
+        "gcr.io/google_containers/defaultbackend:1.4"
+    if arch() == 's390x':
+        context['defaultbackend_image'] = \
+            "gcr.io/google_containers/defaultbackend-s390x:1.4"
+
     # Render the default http backend (404) replicationcontroller manifest
     manifest = addon_path.format('default-http-backend.yaml')
     render('default-http-backend.yaml', manifest, context)

cluster/juju/layers/kubernetes-worker/templates/default-http-backend.yaml

@@ -17,7 +17,7 @@ spec:
         # Any image is permissable as long as:
         # 1. It serves a 404 page at /
         # 2. It serves 200 on a /healthz endpoint
-        image: gcr.io/google_containers/defaultbackend:1.0
+        image: {{ defaultbackend_image }}
         livenessProbe:
           httpGet:
             path: /healthz