Assignment

We encountered an issue with our Nginx and PHP-FPM setup on the Kubernetes cluster this morning, which halted its functionality. Investigate and rectify the issue:

The pod name is nginx-phpfpm and configmap name is nginx-config. Identify and fix the problem.

Once resolved, copy /home/thor/index.php file from the jump host to the nginx-container within the nginx document root. After this, you should be able to access the website using Website button on the top bar.

Note: The kubectl utility on the jump-host has been configured to work with the Kubernetes cluster.

Solution

Troubleshoot nginx + php-fpm — `nginx-phpfpm` (confirmed fix)

Root cause (confirmed from the live spec)

The nginx config and the two container mounts don't agree on the document root:

Source	Path
nginx config `root`	`/var/www/html`
`nginx-container` shared-files mount	`/var/www/html` ✓
`php-fpm-container` shared-files mount	`/usr/share/nginx/html` ✗ mismatch

nginx forwards PHP requests to php-fpm with SCRIPT_FILENAME = $document_root$fastcgi_script_name → /var/www/html/index.php. But in the php-fpm container the shared volume is mounted at /usr/share/nginx/html, so the path /var/www/html/index.php doesn't exist there and php-fpm returns "File not found." The two containers share the same emptyDir volume, but at different paths, so they aren't actually sharing the document root.

Fix: change the php-fpm container's shared-files mountPath from /usr/share/nginx/html to /var/www/html, so both containers — and the nginx root, and the FastCGI SCRIPT_FILENAME — all reference the same path.

Step 1 — Recreate the pod with the corrected mountPath

A pod's volumeMounts are immutable in place, so delete and re-create. This heredoc is your live spec (from last-applied-configuration) with only the php-fpm mountPath fixed:

kubectl delete pod nginx-phpfpm

kubectl apply -f - <<'EOF'
apiVersion: v1
kind: Pod
metadata:
  name: nginx-phpfpm
  namespace: default
  labels:
    app: php-app
spec:
  volumes:
    - name: shared-files
      emptyDir: {}
    - name: nginx-config-volume
      configMap:
        name: nginx-config
  containers:
    - name: php-fpm-container
      image: php:7.2-fpm-alpine
      volumeMounts:
        - name: shared-files
          mountPath: /var/www/html          # FIXED: was /usr/share/nginx/html
    - name: nginx-container
      image: nginx:latest
      volumeMounts:
        - name: shared-files
          mountPath: /var/www/html
        - name: nginx-config-volume
          mountPath: /etc/nginx/nginx.conf
          subPath: nginx.conf
EOF

Step 2 — Copy the PHP file into the shared document root

kubectl cp /home/thor/index.php nginx-phpfpm:/var/www/html/index.php -c nginx-container

Copy into /var/www/html (the now-consistent root) via the nginx container. Because the volume is shared at the same path in both containers, php-fpm sees the file too and can execute it.

How it works

Why the mismatch broke it even though the pod was "Running"

Both containers were healthy (2/2 Running) — this wasn't a crash. The failure was purely at request time: nginx served on port 8099, matched .php, and handed php-fpm an absolute path (/var/www/html/...) that was valid in nginx's filesystem but pointed at nothing in php-fpm's. FastCGI passes a path string, not a file handle, so both containers must resolve that same absolute path to the same bytes — which only happens if the shared volume is mounted at the identical path in each. Aligning php-fpm's mount to /var/www/html closes that gap.

Why copy after recreating

Recreating the pod starts with a fresh empty shared-files volume, so index.php is copied after the pod is Running. It then lives in the shared root for the pod's lifetime and is visible to both containers.

Note on the listen port

The nginx config listens on 8099 (not 80), with root /var/www/html. Any Service exposing this app must target port 8099 — the Website button relies on that mapping. This task doesn't ask you to change the Service, just to fix the pod and drop in the file.

Verify

# Pod healthy after recreate
kubectl get pod nginx-phpfpm

# File present in the shared root, visible from BOTH containers
kubectl exec nginx-phpfpm -c nginx-container   -- ls -l /var/www/html/index.php
kubectl exec nginx-phpfpm -c php-fpm-container -- ls -l /var/www/html/index.php

# App renders the PHP page (nginx listens on 8099)
kubectl exec nginx-phpfpm -c nginx-container -- curl -s http://localhost:8099/index.php | head

Expected — nginx-phpfpm READY 2/2, index.php visible from both containers under /var/www/html, and the curl returning the rendered page. The Website button then loads the site.

The key sign the fix worked: ls succeeds from the php-fpm container too. Before the fix it would only appear under /usr/share/nginx/html there, which is exactly why php-fpm couldn't find it at /var/www/html.

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