How to Set Up Auto-Scaling for a WordPress Website on DigitalOcean

Scaling a WordPress website dynamically based on traffic demands is essential for ensuring optimal performance and uptime. In this guide, we will walk you through setting up auto-scaling for a WordPress website on DigitalOcean, with a minimum of 1 node and a maximum of 3 nodes, all attached to a Load Balancer using a tag-based system.

Why Auto-Scaling?

Auto-scaling ensures that your website can handle traffic spikes by adding more nodes when needed and removing them when the load decreases. This helps to optimize costs while maintaining high availability.

Prerequisites

Before getting started, ensure you have:

• A DigitalOcean account
• Basic knowledge of Linux commands

Step 1: Create an Initial WordPress Droplet

1. Log in to your DigitalOcean account.
2. Create a new droplet.
3. Under “Choose an image,” select Marketplace > WordPress.
4. Choose a droplet size (e.g., 2 vCPUs, 4GB RAM for medium traffic).
5. Add an SSH key for secure access.
6. Deploy the droplet and note down its IP address.

After deployment, WordPress will be pre-installed, and you can access it at http://your_droplet_ip.

Step 2: Convert Your WordPress Droplet into a Custom Image

Once WordPress is fully configured and ready to use, create a snapshot:

1. Navigate to Droplets > Your Droplet > Snapshots.
2. Click Take a Snapshot and name it wordpress-image.

This snapshot will be used to create new auto-scaled nodes.

Step 3: Configure Auto-Scaling

1. Go to Droplets > Create > Autoscale Group.
2. Define the auto-scaling parameters:
   • Minimum Nodes: 1
   • Maximum Nodes: 3
   • Scaling Rule: Add a node when CPU usage > 70% for 5 minutes.
3. Select your custom image (wordpress-image) as the base.
4. Add a tag (e.g., wordpress-autoscale).

Step 4: Set Up Load Balancer

1. Go to Networking > Load Balancers > Create Load Balancer.
2. Configure the load balancer:
   • Forwarding Rules:
     • Port 80 → Port 80
     • Port 443 → Port 443
   • Droplet Tag: Select wordpress-autoscale.
3. Enable Health Checks.
4. Deploy the Load Balancer.

Now, whenever new droplets are created, they will be automatically attached to the Load Balancer.

Step 5: Auto-Scaling in Action

• When traffic increases, a new droplet (node2) will be created from the wordpress-image snapshot.
• Node2 automatically joins the load balancer due to the wordpress-autoscale tag.
• Since all WordPress files are stored locally on each droplet, they will remain accessible within the instance.
• When traffic decreases, extra nodes are removed automatically.