Deployment guide

This guide will walk you through the process of deploying Epsio in your GCP environment.

Before you begin

Before proceeding with the deployment guide, ensure that you have the following:

• A VM instance to run epsio on with:
  • Network access to your PostgreSQL instance.
  • docker, docker compose plugin and zip installed on it
• A PostgreSQL Database with version 10+.

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1. Launch Epsio in your VM

After you sign up, a wizard will appear and walk you through the stages of deployment.

Choose the architecture of your VM:

Run the displayed command in your VM:

Wait until Epsio is successfully deployed, and then proceed to the next step.

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2. Connect Epsio to your database

The next step will be to configure your database and connect it to Epsio.

Open a connection to your database and follow the steps below.

Create a database user for Epsio's exclusive use:

CREATE USER epsio_user WITH PASSWORD '<password>';

Create a schema for Epsio

CREATE SCHEMA IF NOT EXISTS epsio;
GRANT CREATE, USAGE ON SCHEMA epsio TO epsio_user;
GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA epsio TO epsio_user;

Grant user permissions
Grant the epsio_user read-only access to all tables in your schema by running the following commands:

GRANT SELECT ON ALL TABLES IN SCHEMA public TO epsio_user;
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO epsio_user;
GRANT CREATE, USAGE ON SCHEMA public TO epsio_user;

If you plan to access schemas other than the public schema, you'll need to run these commands for each schema.
Replace public with the name of your schema.

Enter the Hostname / IP of the VM you deployed Epsio in:

Enter the credentials of the epsio user you've just created in the wizard and click connect:
You will also need to provide the hostname (or IP address), port and database name.

After connection, Epsio will check that your database is configured correctly and will create the functions under the epsio schema.
Continue to the next step to configure logical replication.

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3. Configure logical replication

3.1 Check if logical replication is enabled

Run the following command to check if your instance is already configured with logical replication:

postgres=> SHOW wal_level;
 wal_level 
-----------
 replica
(1 row)

If the result is logical, it means that logical replication is enabled, skip to set up replication.
If not, follow the steps below to enable logical replication.

3.2 Enable logical replication

GCP Cloud SQLSelf Hosted

Edit your PostgreSQL server.

Edit the Server's flags.

Turn on the cloudsql.logical_decoding flag.

Save the new configuration.

Restart the server.

Verify that the wal_level parameter is set to "logical".

SHOW wal_level;
 wal_level
-------------------------
    logical
    (1 row)

To enable logical replication in a PostgreSQL database, you need to set the wal_level parameter in your database configuration to logical. For standard PostgreSQL installations, you can do this by either:

• Method 1: Adding a wal_level = logical line to the postgresql.conf file.
• Method 2: Running ALTER SYSTEM SET wal_level = logical;;

Optional: Set the max_slot_wal_keep_size parameter to 4096 to limit the amount of WAL data that is retained for logical replication slots. (Postgres 13+)

Restart your database for the changes to take effect.

Verify that the wal_level parameter is set to "logical".

SHOW wal_level;
 wal_level
-------------------------
    logical
    (1 row)

3.3 Set up replication

Next, you'll need to set up replication by running the following commands in your database:

CREATE PUBLICATION epsio_publication;
CREATE PUBLICATION epsio_command_publication;

ALTER USER epsio_user WITH REPLICATION;

Once finished, click on the "Validate Configuration" and Epsio will verify that logical replication is set up correctly.

Congratulations! You've successfully enabled logical replication in your database.

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Once Epsio successfully connects to your database, you'll be redirected to the Epsio dashboard.

You are set to go and can create your first view. Visit the create_view for further details.