At Scalingo, all databases addons plans are identified using a name made of two or three parts separated by a dash (-). This name is made of:

1. a database type : postgresql
2. a class : either sandbox, starter or business (learn more about classes)
3. a size : specifying the amount of RAM available with the plan, in MB (only for starter and business classes).

You can change your PostgreSQL® for Scalingo addon plan whenever you want. The operation is launched instantly, no manual input is required.

The impact on your application and the downtime vary depending on several factors such as the current plan being used and the one you wish to change for (see below for further information).

Understanding the Plan Change Process

From Starter to Starter

When changing the size of a Starter plan, the platform reboots the existing instance with the new size. This leads to a small service interruption during which the database is not available. This shouldn’t exceed a few seconds though.

From Starter to Business

When changing for a Business plan, the platform first starts a follower instance with the targeted size. If necessary, it then reboots the primary instance with the targeted size. There should be no downtime at all, thanks to the failover mechanism included with the Business plan.

From Business to Starter

When changing for a lower class, the platform first powers the follower instance off. When necessary, the remaining primary instance is rebooted with the targeted new size. This can lead to a small service interruption during which the database is not available. This shouldn’t exceed a few seconds though.

From Business to Business

When changing the size of a Business plan, the platform first reboots the primary instance with the targeted new size. It then reboots the follower instance with the targeted new size. There’s no downtime during this operation, thanks to the failover mechanism included in the Business plan.

Using the Dashboard

1. From your web browser, open your dashboard
2. Click on the application for which you want to scale the Scalingo for PostgreSQL® addon
3. Click on the Resources tab
4. Locate the Addons block and click on the … button
5. From the dropdown menu, select Change plan
6. Select the new plan
7. Click the Finish button
8. Validate by clicking the Confirm plan change button

Using the Command Line

1. Make sure you have correctly setup the Scalingo command line tool
2. From the command line, list the plans available for postgresql:

   scalingo addons-plans postgresql
   

   The output should look like this:

   +----------------------------+---------------+
   |             ID             |     NAME      |
   +----------------------------+---------------+
   | postgresql-sandbox         | Sandbox       |
   | postgresql-starter-512     | Starter 512M  |
   | postgresql-starter-1024    | Starter 1G    |
   ...
   

3. Locate the ID corresponding to the plan you want to scale to (for example postgresql-business-1024)
4. Change plan using the addons-upgrade sub-command:

   scalingo --app my-app addons-upgrade postgresql <plan_ID>
   

   The output should look like this:

   -----> Addon ad-d0aa540a-5ed2-41f8-8bbe-91e3aff6623b has been upgraded
          Message from addon provider: Database plan is being changed
   

Using the Terraform Provider

1. Update the plan property of the corresponding Resource block in your Terraform file to scale the addon:

   resource "scalingo_addon" "my-db" {
     provider_id = "postgresql"
     plan = "postgresql-business-1024"
     app = "${scalingo_app.my-app.id}"
   }
   

   In this example, we switch the my-db resource attached to the my-app application to a PostgreSQL Business 1024 addon.

2. Run terraform plan and check if the result looks good
3. If so, run terraform apply