Amazon Aurora PostgreSQL RDS feature snapshot

A high-level look at Stitch's Amazon Aurora PostgreSQL RDS (v1.0) integration, including release status, useful links, and the features supported in Stitch.

STITCH
Release Status Released Supported By

Stitch

Stitch Plan

Free

Supported Versions

9.3+; 10.6+ for binlog

Singer GitHub Repository

Postgres Repository

CONNECTION METHODS
SSH Connections

Supported

SSL Connections

Supported

REPLICATION SETTINGS
Anchor Scheduling

Supported

Advanced Scheduling

Supported

Table-level Reset

Supported

Configurable Replication Methods

Supported

REPLICATION METHODS
Log-based Replication

Supported

Key-based Replication

Supported

Full Table Replication

Supported

DATA SELECTION
Table Selection

Supported

Column Selection

Supported

View Replication

Supported

TRANSPARENCY
Extraction Logs

Supported

Loading Reports

Supported

Connecting Amazon Aurora PostgreSQL RDS

Amazon Aurora PostgreSQL RDS setup requirements

To set up Amazon Aurora PostgreSQL RDS in Stitch, you need:

  • Permissions in Amazon Web Services (AWS) that allow you to:

    • Create/manage Security Groups, which is required to whitelist Stitch’s IP addresses.
    • View database details, which is required for retrieving the database’s connection details.
  • Permissions in PostgreSQL that allow you to create users. This is required to create a database user for Stitch.

  • If using Log-based Incremental Replication, you’ll need:

    • A database running Aurora PostgreSQL 10.6 or greater. This is required to use wal2json, the plugin Stitch uses to perform Log-based Incremental Replication. Amazon introduced support for wal2json in version 10.6 of their Aurora PostgreSQL engine.
    • The rds_superuser role in your Amazon Aurora PostgreSQL RDS database, if you want to use Log-based Replication. This role is required to grant the rds_replication privilege to Stitch’s database user.
    • To connect to the master instance. Log-based replication will only work on master instances due to a feature gap in PostgreSQL 10. Based on their forums, PostgreSQL is working on adding support for using logical replication on a read replica to a future version.
  • If you’re not using Log-based Incremental Replication, you’ll need:

    • A database running PostgreSQL 9.3.x or greater. PostgreSQL 9.3.x is the minimum version Stitch supports for PostgreSQL integrations.
    • To verify if the database is a read replica, or follower. While we always recommend connecting a replica over a production database, this also means you may need to verify some of its settings - specifically the max_standby_streaming_delay and max_standby_archive_delay settings - before connecting it to Stitch. We recommend setting these parameters to 8-12 hours for an initial replication job, and then decreasing them afterwards.

Step 1: Configure database connection settings

In this step, you’ll configure the database server to allow traffic from Stitch to access it. There are two ways to connect your database:

  • A direct connection will work if your database is publicly accessible.
  • An SSH tunnel is required if your database isn’t publicly accessible. This method uses a publicly accessible instance, or an SSH server, to act as an intermediary between Stitch and your database. The SSH server will forward traffic from Stitch through an encrypted tunnel to the private database.

Click the option you’re using below and follow the instructions.

For Stitch to successfully connect with your database instance, you’ll need to add our IP addresses to the appropriate Security Group via the AWS management console.

Security Groups must reside in the same VPC as the instance. Use the instructions below to create a security group for Stitch and grant access to the VPC.

  1. Log into your AWS account.
  2. Navigate to the Security Group Management page, typically Services > Compute > EC2.
  3. Click the Security Groups option, under Network & Security in the menu on the left side of the page.
  4. Click Create Security Group.
  5. In the window that displays, fill in the fields as follows:
    • Security group name: Enter a unique name for the Security Group. For example: Stitch
    • Description: Enter a description for the security group.
    • VPC: Select the VPC that contains the database you want to connect to Stitch. Note: The Security Group and database must be in the same VPC, or the connection will fail.
  6. In the Inbound tab, click Add Rule.
  7. Fill in the fields as follows:
    • Type: Select Custom TCP Rule
    • Port Range: Enter the port your database uses. (5432 by default)
    • CIDR, IP or Security Group: Enter one of the IP addresses listed below:

      • 52.23.137.21/32

      • 52.204.223.208/32

      • 52.204.228.32/32

      • 52.204.230.227/32

  8. Click Add Rule to add an additional Inbound rule.
  9. Repeat steps 6-8 until all the IP addresses above have been added:

    Whitelisting Stitch IP addresses through Inbound Security Group rules

  10. When finished, click Create to create the Security Group.
  1. Follow the steps in the Setting up an SSH Tunnel for a database in Amazon Web Services guide to set up an SSH tunnel for Amazon Aurora PostgreSQL RDS.
  2. Complete the steps in this guide after the SSH setup is complete.

Step 2: Create a Stitch database user

Next, you’ll create a dedicated database user for Stitch. This will ensure Stitch is visible in any logs or audits, and allow you to maintain your privilege hierarchy.

Your organization may require a different process, but the simplest way to create this user is to execute the following query when logged into the Amazon Aurora PostgreSQL RDS database as a user with the right to grant privileges.

Note: The user performing this step should also own the schema(s) that Stitch is being granted access to.

  1. Log into your database.
  2. Create a database user named stitch, replacing <password> with a password:

    CREATE USER stitch WITH ENCRYPTED PASSWORD '<password>'
    
  3. Grant the stitch user CONNECT privileges to the database, replacing <database_name> with the name of a database you want to connect Stitch to:

    GRANT CONNECT ON DATABASE <database_name> TO stitch
    
  4. Grant the stitch user schema usage privileges, replacing <schema_name> with the name of a schema you want to replicate data from:

    GRANT USAGE ON SCHEMA <schema_name> TO stitch
    
  5. Grant the stitch user SELECT privileges on the tables in the schema:

    GRANT SELECT ON ALL TABLES IN SCHEMA <schema_name> TO stitch
    
  6. Alter the schema’s default privileges to grant SELECT privileges on tables to stitch. This is required to ensure that objects created in the schema after connecting to Stitch will remain accessible to the stitch user:

    ALTER DEFAULT PRIVILEGES IN SCHEMA <schema_name> GRANT SELECT ON TABLES TO stitch
    
  7. If you want to replicate data from multiple databases or schemas, repeat steps 3 - 6 as needed.

See the Privileges list tab for an explanation of why these permissions are required by Stitch.

In the table below are the database user privileges Stitch requires to connect to and replicate data from a Amazon Aurora PostgreSQL RDS database.

Privilege name Reason for requirement
CONNECT

Required to connect successfully to the specified database.

USAGE

Required to access the objects contained in the specified schema.

SELECT

Required to select rows from tables in the specified schema.

ALTER DEFAULT PRIVILEGES

Required to ensure that objects created in the schema after connecting to Stitch will be accessible by the Stitch database user.

rds_replication

Required to allow the Stitch database user to use logical (Log-based) replication. The rds_superuser role is required to grant this privilege.

Step 3: Configure Log-based Incremental Replication

While Log-based Incremental Replication is the most accurate and efficient method of replication, using this replication method may, at times, require manual intervention or impact the source database’s performance. Refer to the Log-based Incremental Replication documentation for more info.

You can also use one of Stitch’s other Replication Methods, which don’t require any database configuration. Replication Methods can be changed at any time.

In this section:

Step 3.1: Configure the DB cluster parameter group

In this step, you’ll configure the required parameters in the database’s DB cluster parameter group and enable Log-based Incremental Replication.

Note: Modifications must be made to the DB Cluster Parameter Group associated with the database. This is because the parameters required to enable Log-based Incremental do not exist in Database Parameter Groups.

  1. Sign into the AWS Console, if needed.
  2. Navigate to the RDS option.
  3. On the RDS Dashboard page, click the Databases option on the left side of the page. This will open the RDS Databases page.

  4. In the list of databases, locate and click on the database (not the cluster) you want to connect to Stitch. This will open the Database Details page.

  5. Scroll down to the details section.
  6. Click the Configuration tab and locate the DB cluster parameter group field.
  7. Click the parameter group link. This will open the settings page for the DB cluster parameter group.
  8. Click the Edit parameters button.
  9. Locate the parameters in the list below, and enter the required values into the Values column:

    • rds.logical_replication: 1

    • max_replication_slots: 5

    • max_wal_senders: 5

    Note: For max_replication_slots and max_wal_senders, Amazon’s default value of 5 should be sufficient unless you have a large number of read replicas.

    See the Server settings list tab for more info on these settings.

  10. When finished, click the Save changes button.

In the table below are the names, required values, and descriptions of the server settings you must define.

Setting Value Description
rds.logical_replication 1

Required to use Log-based Replication; available on PostgreSQL versions 9.4 and higher. Enables logical (log-based) replication for the database server.

max_replication_slots 5

Required to use Log-based Replication; available on PostgreSQL versions 9.4 and higher. Specifies the maximum number of replication slots that the server can support.

This must be greater than 1. If you have a large number of replica databases, you may want to increase the value of this parameter. Typically, Amazon’s default value of 5 should be sufficient.

max_wal_senders 5

Available on PostgreSQL versions 9.4 and higher. Specifies the maximum number of concurrent connections from standby servers or streaming base backup clients (the maximum number of simultaneously running WAL sender processes).

If you have a large number of replica databases, you may want to define this setting during setup. Typically, Amazon’s default value of 5 should be sufficient.

Step 3.2: Define the backup retention period

The backup retention period setting defines the number of days for which automated backups are retained. This ensures that data can still be replicated even if a job is interrupted, there’s database or Stitch downtime, etc.

  1. Navigate back to the Databases page by using the menu on the left side of the page.

  2. Select the instance you’re connecting to Stitch.
  3. Click the Modify button.
  4. On the Modify DB Instance page, scroll down to the Backup section.

  5. Set Backup retention period to anything greater than 1 day:

    A backup retention period setting of 1 day for an RDS instance in the AWS console

Step 3.3: Apply parameter changes and reboot the database

  1. Scroll to the bottom of the Databases page and click Continue.
  2. The next page will display a summary of the modifications made to the database. In the Scheduling of Modifications section, select the Apply Immediately option.
  3. Click Modify DB Instance to apply the changes.
  4. Navigate to the Instance Details page and locate the Parameter group. Initially, the Parameter group should say applying.

    When it changes to pending-reboot, you can reboot the database and apply the changes.

  5. Scroll up to the top of the page and locate the Instance actions menu.
  6. In this menu, click Reboot.
  7. On the next page, click Reboot to confirm you want to reboot the instance.

Rebooting the instance will take a few minutes. When the status of the parameter group changes to in-sync and the DB instance status (located at the top of the Instance Details page) changes to available, the reboot will be complete:

An "Available" DB instance status for an RDS instance in the AWS console

Step 3.4: Create a replication slot

Next, you’ll create a dedicated logical replication slot for Stitch. In PostgreSQL, a logical replication slot represents a stream of database changes that can then be replayed to a client in the order they were made on the original server. Each slot streams a sequence of changes from a single database.

Note: Replication slots are specific to a given database in a cluster. If you want to connect multiple databases - whether in one integration or several - you’ll need to create a replication slot for each database.

  1. Log into the master database as a superuser.
  2. Using the wal2json plugin, create a logical replication slot:
    • If you’re connecting multiple databases, you’ll need to run this command for every database you want to connect, replacing <raw_database_name> with the name of the database:

      SELECT *
      FROM pg_create_logical_replication_slot('stitch_<raw_database_name>', 'wal2json');
      

      This will create a replication slot named stitch_<raw_database_name>.

    • If you’re connecting a single database, run the following command:

      SELECT *
      FROM pg_create_logical_replication_slot('stitch', 'wal2json');
      

      This will create a replication slot named stitch.

  3. Log in as the Stitch user and verify you can read from the replication slot, replacing <replication_slot_name> with the name of the replication slot:

    SELECT COUNT(*)
    FROM pg_logical_slot_peek_changes('<replication_slot_name>', null, null);
    

    If connecting multiple databases, you should verify that the Stitch user can read from each of the replication slots you created.

Note: wal2json is required to use Log-based replication in Stitch for PostgreSQL-backed databases. wal2json is included by default and enabled in Step 3.1 by defining the rds.logical_replication parameter.

Step 4: Connect Stitch

In this step, you’ll complete the setup by entering the database’s connection details and defining replication settings in Stitch.

Step 4.1: Locate the database connection details in AWS

  1. Sign into the AWS Console, if needed.
  2. Navigate to the RDS option.
  3. On the RDS Dashboard page, click the Databases option on the left side of the page. This will open the RDS Databases page.

  4. In the list of databases, locate and click on the database (not the cluster) you want to connect to Stitch. This will open the Database Details page.

  5. On the Database Details page, scroll down to the Connectivity & security section.

  6. Locate the following fields:
    • Endpoint
    • DB Name: This field contains the name of the database used to launch the instance. You’ll only need this info if you want to connect this specific database to Stitch.

      You can connect this database to Stitch, or another database within Amazon Aurora PostgreSQL RDS.

    • Port: This is the port used by the database.

Leave this page open for now - you’ll need it to complete the setup.

Step 4.2: Define the database connection details in Stitch

  1. If you aren’t signed into your Stitch account, sign in now.
  2. On the Stitch Dashboard page, click the Add Integration button.

  3. Locate and click the PostgreSQL icon.
  4. Fill in the fields as follows:

    • Integration Name: Enter a name for the integration. This is the name that will display on the Stitch Dashboard for the integration; it’ll also be used to create the schema in your destination.

      For example, the name “Stitch Amazon Aurora PostgreSQL RDS” would create a schema called stitch_amazon_aurora_postgresql_rds in the destination. Note: The schema name cannot be changed after the integration is saved.

    • Host (Endpoint): Paste the Endpoint address from the Amazon Aurora PostgreSQL RDS Details page in AWS into this field. Don’t include the port number, if it’s appended to the end of the endpoint string - this will cause errors.

    • Port: Enter the port used by the instance. The default is 5432.

    • Username: Enter the Stitch Amazon Aurora PostgreSQL RDS database user’s username.

    • Password: Enter the password for the Stitch Amazon Aurora PostgreSQL RDS database user.

    • Database: Enter the name of the Amazon Aurora PostgreSQL RDS database you want to connect to Stitch. Stitch will ‘find’ all databases you give the Stitch user access to - a default database is only used to complete the connection. This is required for Amazon Aurora PostgreSQL RDS integrations.

    • Include PostgreSQL schema names in destination tables: Checking this setting will include schema names from the source database in the destination table name - for example: <source_schema_name>__<table_name>.

      Stitch loads all selected replicated tables to a single schema, preserving only the table name. If two tables canonicalize to the same name - even if they’re in different source databases or schemas - name collision errors can arise. Checking this setting can prevent these issues.

      Note: This setting can not be changed after the integration is saved. Additionally, this setting may create table names that exceed your destination’s limits. For more info, refer to the Database Integration Table Name Collisions guide.

Step 4.3: Define the SSH connection details

If you’re using an SSH tunnel to connect your Amazon Aurora PostgreSQL RDS database to Stitch, you’ll also need to define the SSH settings. Refer to the Setting up an SSH Tunnel for a database in Amazon Web Services guide for assistance with completing these fields.

  1. Click the SSH Tunnel checkbox.

  2. Fill in the fields as follows:

    • SSH Host: Paste the Public DNS of the SSH sever (EC2 instance) into this field. Refer to the Amazon SSH guide for instructions on retrieving this info.

    • SSH Port: Enter the SSH port of the SSH server (EC2 instance) into this field. This will usually be 22.

    • SSH User: Enter the Stitch Linux (SSH) user’s username.

Step 4.4: Define the SSL connection details

Click the Connect using SSL checkbox if you’re using an SSL connection. Note: The database must support and allow SSL connections for this setting to work correctly.

Step 4.5: Define Log-based Replication setting

In the Log-based Replication section, you can set this as the integration’s default Replication Method.

When enabled, tables that are set to replicate will use Log-based Incremental Replication by default. If you don’t want a table to use Log-based Incremental Replication, you can change it in the Table Settings page for that table.

If this setting isn’t enabled, you’ll have to select a Replication Method for each table you set to replicate.

Step 4.6: Create a replication schedule

In the Replication Frequency section, you’ll create the integration’s replication schedule. An integration’s replication schedule determines how often Stitch runs a replication job, and the time that job begins.

Amazon Aurora PostgreSQL RDS integrations support the following replication scheduling methods:

To keep your row usage low, consider setting the integration to replicate less frequently. See the Understanding and Reducing Your Row Usage guide for tips on reducing your usage.

Step 5: Select data to replicate

The last step is to select select the tables and columns you want to replicate.

When you track a table, you’ll also need to define its Replication Method and, if using Key-based Incremental Replication, its Replication Key.

You can select tables and columns by:

  1. In the Integration Details page, click the Tables to Replicate tab.
  2. Locate a table you want to replicate.
  3. Click the checkbox next to the object’s name. A green checkmark means the object is set to replicate.
  4. If there are child objects, they’ll automatically display and you’ll be prompted to select some. Note: When you track a table, by default all columns will also be tracked.
  5. After you set a table to replicate, a page with the table’s columns will display. De-select columns if needed.

  6. In the Settings page, define the table’s Replication Method and, if using Key-based Incremental Replication, its Replication Key.

  7. Repeat this process for every table you want to replicate.

  8. Click the Finalize Your Selections button to save your data selections.

Initial and historical replication jobs

After you finish setting up Amazon Aurora PostgreSQL RDS, its Sync Status may show as Pending on either the Stitch Dashboard or in the Integration Details page.

For a new integration, a Pending status indicates that Stitch is in the process of scheduling the initial replication job for the integration. This may take some time to complete.

Free historical data loads

The first seven days of replication, beginning when data is first replicated, are free. Rows replicated from the new integration during this time won’t count towards your quota. Stitch offers this as a way of testing new integrations, measuring usage, and ensuring historical data volumes don’t quickly consume your quota.



Questions? Feedback?

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