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Enable Logical Replication

Crunchy Bridge comes with logical replication enabled by default. Ensure that the settings below are configured correctly. If not, adjust them accordingly.
SHOW wal_level; -- should be logical
SHOW max_wal_senders; -- should be 10
SHOW max_replication_slots; -- should be 10

Creating PeerDB User and Granting permissions

Connect to your Crunchy Bridge Postgres through the postgres user and run the below commands:
  1. Create a dedicated user for PeerDB:
    1.      CREATE USER peerdb_user PASSWORD 'some-password';
      
  2. Grant schema-level, read-only access to the user you created in the previous step. The following example shows permissions for the public schema. Repeat these commands for each schema containing tables you want to replicate:
    1.      GRANT USAGE ON SCHEMA "public" TO peerdb_user;
           GRANT SELECT ON ALL TABLES IN SCHEMA "public" TO peerdb_user;
           ALTER DEFAULT PRIVILEGES IN SCHEMA "public" GRANT SELECT ON TABLES TO peerdb_user;
      
  3. Grant replication privileges to the user:
    1.      ALTER ROLE peerdb_user REPLICATION;
      
  4. Create a publication with the tables you want to replicate. We strongly recommend only including the tables you need in the publication to avoid performance overhead.
    Any table included in the publication must either have a primary key defined or have its replica identity configured to FULL.
    1. To create a publication for specific tables:
          CREATE PUBLICATION peerdb_publication FOR TABLE table_to_replicate, table_to_replicate2;
    
    1. To create a publication for all tables in a specific schema:
            CREATE PUBLICATION peerdb_publication FOR TABLES IN SCHEMA "public";
      
    The peerdb_publication publication will contain the set of change events generated from the specified tables, and will later be used to create the MIRROR (replication).
The PeerDB user must not be restricted by RLS policies, as it can lead to missing data. You can disable RLS policies for the user by running the below command:
ALTER USER peerdb_user BYPASSRLS;

Safe list PeerDB Cloud IPs

If you are using PeerDB Cloud safelist the public IPs of your PeerDB Cloud instance by adding the Firewall Rules in Crunchy Bridge.

Where to find Firewall Rules in Crunchy Bridge?

Add the 3 Firewall Rules for PeerDB Cloud

Create Crunchy Bridge Peer in PeerDB

Through the PeerDB UI, create the Crunchy Bridge Postgres Peer using the peerdb_user that you created in the previous step.

Create peer drop down

Create Crunchy Bridge Peer