How To Deploy a PHP Application with Kubernetes on Ubuntu 18.04

The author selected Electronic Frontier Foundation to receive a donation as part of the Write for DOnations program.

Introduction

Kubernetes is an open source container orchestration system. It allows you to create, update, and scale containers without worrying about downtime.

To run a PHP application, Nginx acts as a proxy to PHP-FPM. Containerizing this setup in a single container can be a cumbersome process, but Kubernetes will help manage both services in separate containers. Using Kubernetes will allow you to keep your containers reusable and swappable, and you will not have to rebuild your container image every time there’s a new version of Nginx or PHP.

In this tutorial, you will deploy a PHP 7 application on a Kubernetes cluster with Nginx and PHP-FPM running in separate containers. You will also learn how to keep your configuration files and application code outside the container image using DigitalOcean’s Block Storage system. This approach will allow you to reuse the Nginx image for any application that needs a web/proxy server by passing a configuration volume, rather than rebuilding the image.

Prerequisites

• A basic understanding of Kubernetes objects. Check out our Introduction to Kubernetes article for more information.
• A Kubernetes cluster running on Ubuntu 18.04. You can set this up by following the How To Create a Kubernetes 1.14 Cluster Using Kubeadm on Ubuntu 18.04 tutorial.
• A DigitalOcean account and an API access token with read and write permissions to create our storage volume. If you don’t have your API access token, you can create it from here.
• Your application code hosted on a publicly accessible URL, such as Github.

Step 1 — Creating the PHP-FPM and Nginx Services

In this step, you will create the PHP-FPM and Nginx services. A service allows access to a set of pods from within the cluster. Services within a cluster can communicate directly through their names, without the need for IP addresses. The PHP-FPM service will allow access to the PHP-FPM pods, while the Nginx service will allow access to the Nginx pods.

Since Nginx pods will proxy the PHP-FPM pods, you will need to tell the service how to find them. Instead of using IP addresses, you will take advantage of Kubernetes’ automatic service discovery to use human-readable names to route requests to the appropriate service.

To create the service, you will create an object definition file. Every Kubernetes object definition is a YAML file that contains at least the following items:

• apiVersion: The version of the Kubernetes API that the definition belongs to.
• kind: The Kubernetes object this file represents. For example, a pod or service.
• metadata: This contains the name of the object along with any labels that you may wish to apply to it.
• spec: This contains a specific configuration depending on the kind of object you are creating, such as the container image or the ports on which the container will be accessible from.

First you will create a directory to hold your Kubernetes object definitions.

SSH to your master node and create the definitions directory that will hold your Kubernetes object definitions.

mkdir definitions

Navigate to the newly created definitions directory:

cd definitions

Make your PHP-FPM service by creating a php_service.yaml file:

nano php_service.yaml

Set kind as Service to specify that this object is a service:

apiVersion: v1
kind: Service

Name the service php since it will provide access to PHP-FPM:

...
metadata:
  name: php

You will logically group different objects with labels. In this tutorial, you will use labels to group the objects into “tiers”, such as frontend or backend. The PHP pods will run behind this service, so you will label it as tier: backend.

...
  labels:
    tier: backend

A service determines which pods to access by using selector labels. A pod that matches these labels will be serviced, independent of whether the pod was created before or after the service. You will add labels for your pods later in the tutorial.

Use the tier: backend label to assign the pod into the back-end tier. You will also add the app: php label to specify that this pod runs PHP. Add these two labels after the metadata section.

...
spec:
  selector:
    app: php
    tier: backend

Next, specify the port used to access this service. You will use port 9000 in this tutorial. Add it to the php_service.yaml file under spec:

...
  ports:
    - protocol: TCP
      port: 9000

Your completed php_service.yaml file will look like this:

apiVersion: v1
kind: Service
metadata:
  name: php
  labels:
    tier: backend
spec:
  selector:
    app: php
    tier: backend
  ports:
  - protocol: TCP
    port: 9000

Hit CTRL + O to save the file, and then CTRL + X to exit nano.

Now that you’ve created the object definition for your service, to run the service you will use the kubectl apply command along with the -f argument and specify your php_service.yaml file.

Create your service:

kubectl apply -f php_service.yaml

This output confirms the service creation:

Output
service/php created

Verify that your service is running:

kubectl get svc

You will see your PHP-FPM service running:

Output
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
kubernetes   ClusterIP   10.96.0.1       <none>        443/TCP    10m
php          ClusterIP   10.100.59.238   <none>        9000/TCP   5m

There are various service types that Kubernetes supports. Your php service uses the default service type, ClusterIP. This service type assigns an internal IP and makes the service reachable only from within the cluster.

Now that the PHP-FPM service is ready, you will create the Nginx service. Create and open a new file called nginx_service.yaml with the editor:

nano nginx_service.yaml

This service will target Nginx pods, so you will name it nginx. You will also add a tier: backend label as it belongs in the back-end tier:

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    tier: backend

Similar to the php service, target the pods with the selector labels app: nginx and tier: backend. Make this service accessible on port 80, the default HTTP port.

...
spec:
  selector:
    app: nginx
    tier: backend
  ports:
  - protocol: TCP
    port: 80

The Nginx service will be publicly accessible to the internet from your Droplet’s public IP address. your_public_ip can be found from your DigitalOcean Control Panel. Under spec.externalIPs, add:

...
spec:
  externalIPs:
  - your_public_ip

Your nginx_service.yaml file will look like this:

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    tier: backend
spec:
  selector:
    app: nginx
    tier: backend
  ports:
  - protocol: TCP
    port: 80
  externalIPs:
  - your_public_ip    

Save and close the file. Create the Nginx service:

kubectl apply -f nginx_service.yaml

You will see the following output when the service is running:

Output
service/nginx created

You can view all running services by executing:

kubectl get svc

You will see both the PHP-FPM and Nginx services listed in the output:

Output
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
kubernetes   ClusterIP   10.96.0.1       <none>        443/TCP    13m
nginx        ClusterIP   10.102.160.47   your_public_ip 80/TCP     50s
php          ClusterIP   10.100.59.238   <none>        9000/TCP   8m

Please note, if you want to delete a service you can run:

kubectl delete svc/service_name

Now that you’ve created your PHP-FPM and Nginx services, you will need to specify where to store your application code and configuration files.

Step 2 — Installing the DigitalOcean Storage Plug-In

Kubernetes provides different storage plug-ins that can create the storage space for your environment. In this step, you will install the DigitalOcean storage plug-in to create block storage on DigitalOcean. Once the installation is complete, it will add a storage class named do-block-storage that you will use to create your block storage.

You will first configure a Kubernetes Secret object to store your DigitalOcean API token. Secret objects are used to share sensitive information, like SSH keys and passwords, with other Kubernetes objects within the same namespace. Namespaces provide a way to logically separate your Kubernetes objects.

Open a file named secret.yaml with the editor:

nano secret.yaml

You will name your Secret object digitalocean and add it to the kube-system namespace. The kube-system namespace is the default namespace for Kubernetes’ internal services and is also used by the DigitalOcean storage plug-in to launch various components.

apiVersion: v1
kind: Secret
metadata:
  name: digitalocean
  namespace: kube-system

Instead of a spec key, a Secret uses a data or stringData key to hold the required information. The data parameter holds base64 encoded data that is automatically decoded when retrieved. The stringData parameter holds non-encoded data that is automatically encoded during creation or updates, and does not output the data when retrieving Secrets. You will use stringData in this tutorial for convenience.

Add the access-token as stringData:

...
stringData:
  access-token: your-api-token

Save and exit the file.

Your secret.yaml file will look like this:

apiVersion: v1
kind: Secret
metadata:
  name: digitalocean
  namespace: kube-system
stringData:
  access-token: your-api-token

Create the secret:

kubectl apply -f secret.yaml

You will see this output upon Secret creation:

Output
secret/digitalocean created

You can view the secret with the following command:

kubectl -n kube-system get secret digitalocean

The output will look similar to this:

Output
NAME           TYPE      DATA      AGE
digitalocean   Opaque    1         41s

The Opaque type means that this Secret is read-only, which is standard for stringData Secrets. You can read more about it on the Secret design spec. The DATA field shows the number of items stored in this Secret. In this case, it shows 1 because you have a single key stored.

Now that your Secret is in place, install the DigitalOcean block storage plug-in:

kubectl apply -f https://raw.githubusercontent.com/digitalocean/csi-digitalocean/master/deploy/kubernetes/releases/csi-digitalocean-v1.1.0.yaml

You will see output similar to the following:

Output
csidriver.storage.k8s.io/dobs.csi.digitalocean.com created
customresourcedefinition.apiextensions.k8s.io/volumesnapshotclasses.snapshot.storage.k8s.io created
customresourcedefinition.apiextensions.k8s.io/volumesnapshotcontents.snapshot.storage.k8s.io created
customresourcedefinition.apiextensions.k8s.io/volumesnapshots.snapshot.storage.k8s.io created
storageclass.storage.k8s.io/do-block-storage created
statefulset.apps/csi-do-controller created
serviceaccount/csi-do-controller-sa created
clusterrole.rbac.authorization.k8s.io/csi-do-provisioner-role created
clusterrolebinding.rbac.authorization.k8s.io/csi-do-provisioner-binding created
clusterrole.rbac.authorization.k8s.io/csi-do-attacher-role created
clusterrolebinding.rbac.authorization.k8s.io/csi-do-attacher-binding created
clusterrole.rbac.authorization.k8s.io/csi-do-snapshotter-role created
clusterrolebinding.rbac.authorization.k8s.io/csi-do-snapshotter-binding created
daemonset.apps/csi-do-node created
serviceaccount/csi-do-node-sa created
clusterrole.rbac.authorization.k8s.io/csi-do-node-driver-registrar-role created
clusterrolebinding.rbac.authorization.k8s.io/csi-do-node-driver-registrar-binding created
error: unable to recognize "https://raw.githubusercontent.com/digitalocean/csi-digitalocean/master/deploy/kubernetes/releases/csi-digitalocean-v1.1.0.yaml": no matches for kind "VolumeSnapshotClass" in version "snapshot.storage.k8s.io/v1alpha1"

For this tutorial, it is safe to ignore the errors.

Now that you have installed the DigitalOcean storage plug-in, you can create block storage to hold your application code and configuration files.

Step 3 — Creating the Persistent Volume

With your Secret in place and the block storage plug-in installed, you are now ready to create your Persistent Volume. A Persistent Volume, or PV, is block storage of a specified size that lives independently of a pod’s life cycle. Using a Persistent Volume will allow you to manage or update your pods without worrying about losing your application code. A Persistent Volume is accessed by using a PersistentVolumeClaim, or PVC, which mounts the PV at the required path.

Open a file named code_volume.yaml with your editor:

nano code_volume.yaml

Name the PVC code by adding the following parameters and values to your file:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: code

The spec for a PVC contains the following items:

• accessModes which vary by the use case. These are:
  • ReadWriteOnce – mounts the volume as read-write by a single node
  • ReadOnlyMany – mounts the volume as read-only by many nodes
  • ReadWriteMany – mounts the volume as read-write by many nodes
• resources – the storage space that you require

DigitalOcean block storage is only mounted to a single node, so you will set the accessModes to ReadWriteOnce. This tutorial will guide you through adding a small amount of application code, so 1GB will be plenty in this use case. If you plan on storing a larger amount of code or data on the volume, you can modify the storage parameter to fit your requirements. You can increase the amount of storage after volume creation, but shrinking the disk is not supported.

...
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi

Next, specify the storage class that Kubernetes will use to provision the volumes. You will use the do-block-storage class created by the DigitalOcean block storage plug-in.

...
  storageClassName: do-block-storage

Your code_volume.yaml file will look like this:

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: code
spec:
  accessModes:
  - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
  storageClassName: do-block-storage

Save and exit the file.

Create the code PVC using kubectl:

kubectl apply -f code_volume.yaml

The following output tells you that the object was successfully created, and you are ready to mount your 1GB PVC as a volume.

Output
persistentvolumeclaim/code created

To view available Persistent Volumes (PV):

kubectl get pv

You will see your PV listed:

Output
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS    CLAIM          STORAGECLASS       REASON    AGE
pvc-ca4df10f-ab8c-11e8-b89d-12331aa95b13   1Gi        RWO            Delete           Bound     default/code   do-block-storage             2m

The fields above are an overview of your configuration file, except for Reclaim Policy and Status. The Reclaim Policy defines what is done with the PV after the PVC accessing it is deleted. Delete removes the PV from Kubernetes as well as the DigitalOcean infrastructure. You can learn more about the Reclaim Policy and Status from the Kubernetes PV documentation.

You’ve successfully created a Persistent Volume using the DigitalOcean block storage plug-in. Now that your Persistent Volume is ready, you will create your pods using a Deployment.

Step 4 — Creating a PHP-FPM Deployment

In this step, you will learn how to use a Deployment to create your PHP-FPM pod. Deployments provide a uniform way to create, update, and manage pods by using ReplicaSets. If an update does not work as expected, a Deployment will automatically rollback its pods to a previous image.

The Deployment spec.selector key will list the labels of the pods it will manage. It will also use the template key to create the required pods.

This step will also introduce the use of Init Containers. Init Containers run one or more commands before the regular containers specified under the pod’s template key. In this tutorial, your Init Container will fetch a sample index.php file from GitHub Gist using wget. These are the contents of the sample file:

<?php
echo phpinfo(); 

To create your Deployment, open a new file called php_deployment.yaml with your editor:

nano php_deployment.yaml

This Deployment will manage your PHP-FPM pods, so you will name the Deployment object php. The pods belong to the back-end tier, so you will group the Deployment into this group by using the tier: backend label:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: php
  labels:
    tier: backend

For the Deployment spec, you will specify how many copies of this pod to create by using the replicas parameter. The number of replicas will vary depending on your needs and available resources. You will create one replica in this tutorial:

...
spec:
  replicas: 1

This Deployment will manage pods that match the app: php and tier: backend labels. Under selector key add:

...
  selector:
    matchLabels:
      app: php
      tier: backend

Next, the Deployment spec requires the template for your pod’s object definition. This template will define specifications to create the pod from. First, you will add the labels that were specified for the php service selectors and the Deployment’s matchLabels. Add app: php and tier: backend under template.metadata.labels:

...
  template:
    metadata:
      labels:
        app: php
        tier: backend

A pod can have multiple containers and volumes, but each will need a name. You can selectively mount volumes to a container by specifying a mount path for each volume.

First, specify the volumes that your containers will access. You created a PVC named code to hold your application code, so name this volume code as well. Under spec.template.spec.volumes, add the following:

...
    spec:
      volumes:
      - name: code
        persistentVolumeClaim:
          claimName: code

Next, specify the container you want to run in this pod. You can find various images on the Docker store, but in this tutorial you will use the php:7-fpm image.

Under spec.template.spec.containers, add the following:

...
      containers:
      - name: php
        image: php:7-fpm

Next, you will mount the volumes that the container requires access to. This container will run your PHP code, so it will need access to the code volume. You will also use mountPath to specify /code as the mount point.

Under spec.template.spec.containers.volumeMounts, add:

...
        volumeMounts:
        - name: code
          mountPath: /code

Now that you have mounted your volume, you need to get your application code on the volume. You may have previously used FTP/SFTP or cloned the code over an SSH connection to accomplish this, but this step will show you how to copy the code using an Init Container.

Depending on the complexity of your setup process, you can either use a single initContainer to run a script that builds your application, or you can use one initContainer per command. Make sure that the volumes are mounted to the initContainer.

In this tutorial, you will use a single Init Container with busybox to download the code. busybox is a small image that contains the wget utility that you will use to accomplish this.

Under spec.template.spec, add your initContainer and specify the busybox image:

...
      initContainers:
      - name: install
        image: busybox

Your Init Container will need access to the code volume so that it can download the code in that location. Under spec.template.spec.initContainers, mount the volume code at the /code path:

...
        volumeMounts:
        - name: code
          mountPath: /code

Each Init Container needs to run a command. Your Init Container will use wget to download the code from Github into the /code working directory. The -O option gives the downloaded file a name, and you will name this file index.php.

Under the install container in spec.template.spec.initContainers, add these lines:

...
        command:
        - wget
        - "-O"
        - "/code/index.php"
        - https://raw.githubusercontent.com/do-community/php-kubernetes/master/index.php

Your completed php_deployment.yaml file will look like this:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: php
  labels:
    tier: backend
spec:
  replicas: 1
  selector:
    matchLabels:
      app: php
      tier: backend
  template:
    metadata:
      labels:
        app: php
        tier: backend
    spec:
      volumes:
      - name: code
        persistentVolumeClaim:
          claimName: code
      containers:
      - name: php
        image: php:7-fpm
        volumeMounts:
        - name: code
          mountPath: /code
      initContainers:
      - name: install
        image: busybox
        volumeMounts:
        - name: code
          mountPath: /code
        command:
        - wget
        - "-O"
        - "/code/index.php"
        - https://raw.githubusercontent.com/do-community/php-kubernetes/master/index.php

Save the file and exit the editor.

Create the PHP-FPM Deployment with kubectl:

kubectl apply -f php_deployment.yaml

You will see the following output upon Deployment creation:

Output
deployment.apps/php created

To summarize, this Deployment will start by downloading the specified images. It will then request the PersistentVolume from your PersistentVolumeClaim and serially run your initContainers. Once complete, the containers will run and mount the volumes to the specified mount point. Once all of these steps are complete, your pod will be up and running.

You can view your Deployment by running:

kubectl get deployments

You will see the output:

Output
NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
php       1         1         1            0           19s

This output can help you understand the current state of the Deployment. A Deployment is one of the controllers that maintains a desired state. The template you created specifies that the DESIRED state will have 1 replicas of the pod named php. The CURRENT field indicates how many replicas are running, so this should match the DESIRED state. You can read about the remaining fields in the Kubernetes Deployments documentation.

You can view the pods that this Deployment started with the following command:

kubectl get pods

The output of this command varies depending on how much time has passed since creating the Deployment. If you run it shortly after creation, the output will likely look like this:

Output
NAME                   READY     STATUS     RESTARTS   AGE
php-86d59fd666-bf8zd   0/1       Init:0/1   0          9s

The columns represent the following information:

• Ready: The number of replicas running this pod.
• Status: The status of the pod. Init indicates that the Init Containers are running. In this output, 0 out of 1 Init Containers have finished running.
• Restarts: How many times this process has restarted to start the pod. This number will increase if any of your Init Containers fail. The Deployment will restart it until it reaches a desired state.

Depending on the complexity of your startup scripts, it can take a couple of minutes for the status to change to podInitializing:

Output
NAME                   READY     STATUS            RESTARTS   AGE
php-86d59fd666-lkwgn   0/1       podInitializing   0          39s

This means the Init Containers have finished and the containers are initializing. If you run the command when all of the containers are running, you will see the pod status change to Running.

Output
NAME                   READY     STATUS            RESTARTS   AGE
php-86d59fd666-lkwgn   1/1       Running   0          1m

You now see that your pod is running successfully. If your pod doesn’t start, you can debug with the following commands:

• View detailed information of a pod:

kubectl describe pods pod-name

• View logs generated by a pod:

kubectl logs pod-name

• View logs for a specific container in a pod:

kubectl logs pod-name container-name

Your application code is mounted and the PHP-FPM service is now ready to handle connections. You can now create your Nginx Deployment.

Step 5 — Creating the Nginx Deployment

In this step, you will use a ConfigMap to configure Nginx. A ConfigMap holds your configuration in a key-value format that you can reference in other Kubernetes object definitions. This approach will grant you the flexibility to reuse or swap the image with a different Nginx version if needed. Updating the ConfigMap will automatically replicate the changes to any pod mounting it.

Create a nginx_configMap.yaml file for your ConfigMap with your editor:

nano nginx_configMap.yaml

Name the ConfigMap nginx-config and group it into the tier: backend micro-service:

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
  labels:
    tier: backend

Next, you will add the data for the ConfigMap. Name the key config and add the contents of your Nginx configuration file as the value. You can use the example Nginx configuration from this tutorial.

Because Kubernetes can route requests to the appropriate host for a service, you can enter the name of your PHP-FPM service in the fastcgi_pass parameter instead of its IP address. Add the following to your nginx_configMap.yaml file:

...
data:
  config : |
    server {
      index index.php index.html;
      error_log  /var/log/nginx/error.log;
      access_log /var/log/nginx/access.log;
      root /code;

      location / {
          try_files $uri $uri/ /index.php?$query_string;
      }

      location ~ \.php$ {
          try_files $uri =404;
          fastcgi_split_path_info ^(.+\.php)(/.+)$;
          fastcgi_pass php:9000;
          fastcgi_index index.php;
          include fastcgi_params;
          fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
          fastcgi_param PATH_INFO $fastcgi_path_info;
        }
    }

Your nginx_configMap.yaml file will look like this:

apiVersion: v1
kind: ConfigMap
metadata:
  name: nginx-config
  labels:
    tier: backend
data:
  config : |
    server {
      index index.php index.html;
      error_log  /var/log/nginx/error.log;
      access_log /var/log/nginx/access.log;
      root /code;
      
      location / {
          try_files $uri $uri/ /index.php?$query_string;
      }

      location ~ \.php$ {
          try_files $uri =404;
          fastcgi_split_path_info ^(.+\.php)(/.+)$;
          fastcgi_pass php:9000;
          fastcgi_index index.php;
          include fastcgi_params;
          fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
          fastcgi_param PATH_INFO $fastcgi_path_info;
        }
    }

Save the file and exit the editor.

Create the ConfigMap:

kubectl apply -f nginx_configMap.yaml

You will see the following output:

Output
configmap/nginx-config created

You’ve finished creating your ConfigMap and can now build your Nginx Deployment.

Start by opening a new nginx_deployment.yaml file in the editor:

nano nginx_deployment.yaml

Name the Deployment nginx and add the label tier: backend:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
  labels:
    tier: backend

Specify that you want one replicas in the Deployment spec. This Deployment will manage pods with labels app: nginx and tier: backend. Add the following parameters and values:

...
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
      tier: backend

Next, add the pod template. You need to use the same labels that you added for the Deployment selector.matchLabels. Add the following:

...
  template:
    metadata:
      labels:
        app: nginx
        tier: backend

Give Nginx access to the code PVC that you created earlier. Under spec.template.spec.volumes, add:

...
    spec:
      volumes:
      - name: code
        persistentVolumeClaim:
          claimName: code

Pods can mount a ConfigMap as a volume. Specifying a file name and key will create a file with its value as the content. To use the ConfigMap, set path to name of the file that will hold the contents of the key. You want to create a file site.conf from the key config. Under spec.template.spec.volumes, add the following:

...
      - name: config
        configMap:
          name: nginx-config
          items:
          - key: config
            path: site.conf

Next, you will specify the image to create your pod from. This tutorial will use the nginx:1.7.9 image for stability, but you can find other Nginx images on the Docker store. Also, make Nginx available on the port 80. Under spec.template.spec add:

...
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80

Nginx and PHP-FPM need to access the file at the same path, so mount the code volume at /code:

...
        volumeMounts:
        - name: code
          mountPath: /code

The nginx:1.7.9 image will automatically load any configuration files under the /etc/nginx/conf.d directory. Mounting the config volume in this directory will create the file /etc/nginx/conf.d/site.conf. Under volumeMounts add the following:

...
        - name: config
          mountPath: /etc/nginx/conf.d

Your nginx_deployment.yaml file will look like this:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
  labels:
    tier: backend
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
      tier: backend
  template:
    metadata:
      labels:
        app: nginx
        tier: backend
    spec:
      volumes:
      - name: code
        persistentVolumeClaim:
          claimName: code
      - name: config
        configMap:
          name: nginx-config
          items:
          - key: config
            path: site.conf
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80
        volumeMounts:
        - name: code
          mountPath: /code
        - name: config
          mountPath: /etc/nginx/conf.d

Save the file and exit the editor.

Create the Nginx Deployment:

kubectl apply -f nginx_deployment.yaml

The following output indicates that your Deployment is now created:

Output
deployment.apps/nginx created

List your Deployments with this command:

kubectl get deployments

You will see the Nginx and PHP-FPM Deployments:

Output
NAME      DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx     1         1         1            0           16s
php       1         1         1            1           7m

List the pods managed by both of the Deployments:

kubectl get pods

You will see the pods that are running:

Output
NAME                     READY     STATUS    RESTARTS   AGE
nginx-7bf5476b6f-zppml   1/1       Running   0          32s
php-86d59fd666-lkwgn     1/1       Running   0          7m

Now that all of the Kubernetes objects are active, you can visit the Nginx service on your browser.

List the running services:

kubectl get services -o wide

Get the External IP for your Nginx service:

Output
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE       SELECTOR
kubernetes   ClusterIP   10.96.0.1       <none>        443/TCP    39m       <none>
nginx        ClusterIP   10.102.160.47   your_public_ip 80/TCP     27m       app=nginx,tier=backend
php          ClusterIP   10.100.59.238   <none>        9000/TCP   34m       app=php,tier=backend

On your browser, visit your server by typing in http://your_public_ip. You will see the output of php_info() and have confirmed that your Kubernetes services are up and running.

Conclusion

In this guide, you containerized the PHP-FPM and Nginx services so that you can manage them independently. This approach will not only improve the scalability of your project as you grow, but will also allow you to efficiently use resources as well. You also stored your application code on a volume so that you can easily update your services in the future.