Set up a Microsoft Fabric Open Mirroring target

In the Microsoft Entra admin center, register an application and add a client secret. Note the Application (client) ID, the Directory (tenant) ID and the secret value. Copy the value when it is shown: Entra shows it only once;

In the Fabric workspace, select Manage access and add the application as a member with the Contributor role or higher;

In the Fabric Admin portal, under Tenant settings → Developer settings, allow service principals to use Fabric APIs, for this application;

Open the mirrored database and, on its Home page, copy the Landing zone URL. It has this form:

https://onelake.dfs.fabric.microsoft.com/<workspace id>/<mirrored database id>/Files/LandingZone

Turn on logical decoding and make room for one replication slot per entity. Restart PostgreSQL afterwards:

ALTER SYSTEM SET wal_level = logical;
ALTER SYSTEM SET max_replication_slots = 20;
ALTER SYSTEM SET max_wal_senders = 20;

Create the user that Gluesync reads with:

CREATE USER gluesync WITH REPLICATION LOGIN PASSWORD '<a strong password>';
GRANT USAGE ON SCHEMA shop TO gluesync;
GRANT SELECT ON ALL TABLES IN SCHEMA shop TO gluesync;

In the Control Plane, select Create your first pipeline, or the + button of the pipeline list if you already have pipelines. The Agents setup wizard opens;

In 1. Setup source, choose the PostgreSQL CDC agent tile and fill Base settings with the Host name / Address, Database name, Username and Password of the source. Select Test and continue. The source appears with a green check mark. Select Next;

In 2. Setup target(s), choose the Microsoft Fabric Open Mirroring agent tile and fill Base settings:

Leave OneLake DFS host, Write _partnerEvents.json at landing-zone root and Request try timeout in seconds at their defaults. Select Test and continue. The target appears with a green check mark. Select Next, enter a Pipeline name and select Finish.

In the pipeline, select Entities. The Add entities page opens with the Object browser. Expand the source schema shop and select the table orders;

Select the field mapping icon of the entity in Selected entities. The Field mapping dialog opens. Under Target, Target Schema (optional — maps to <Schema>.schema folder) is shop and Target Table is orders. Read the target types, and select Confirm;

Select Confirm and continue.

In the pipeline, find the entity. On Hold, select the start options button, the one next to the play button. The Snapshot (copy-only) dialog opens;

Keep Keep and merge under Data already in the target and Standard under Speed;

Select Start snapshot.

Select the play button of the entity. The Sync changes (CDC) dialog opens. Keep Where it stopped, and notice Write method: Standard with the note This target has no bulk load. Select Start entity. The entity becomes Active;

On the source, insert, update and delete rows, and set a column to NULL:

INSERT INTO shop.orders VALUES (100001, 'new-customer', 'new', 12.50, 3, false, 'inserted', ARRAY['x'], now(), current_date, now());
UPDATE shop.orders SET status = 'shipped', amount = 99.99 WHERE id = 5;
DELETE FROM shop.orders WHERE id = 6;
UPDATE shop.orders SET note = NULL WHERE id = 8;

After a few seconds, read the Last rows column of the entity and the Core Hub log. Then wait for Fabric to report the new rows under Monitor replication.

In the pipeline list, select the Fabric icon of the pipeline. The Edit target(s) page opens. Select Advanced settings;

Select Add property, open the Key list and choose the setting, for example Seconds a change file may collect commits before it is published (0 = one file per commit). Enter the value;

Select Test and continue.

Use the secret ID instead of the secret value in Client Secret. The notification reads Entra refused the service principal credentials (AADSTS7000215): the Client Secret is wrong: use the secret value, not the secret ID. Fix: copy the secret value. If it was not saved, add a new secret in Entra;

Change Tenant ID (Entra) to a GUID that is not your tenant. The notification reads Entra refused the service principal credentials (AADSTS900021): AADSTS900021: Requested tenant identifier '<id>' is not valid. Fix: copy the Directory (tenant) ID of the application;

Use a mirrored database ID that does not exist in the landing zone URL. The notification reads Check connection failed. Could not connect to host "https://onelake.dfs.fabric.microsoft.com" as user "<client id>". The landing zone <url> does not exist: check the workspace and the mirrored database item, and that the open mirrored database was created. The same text appears for an unknown workspace ID and for a custom path prefix whose folder does not exist. Fix: copy the URL from the Home page of the mirrored database again;

Cut the URL after the database ID, or end it with another folder. The notification reads '<url>' is not a Fabric Open Mirroring landing zone URL: the mirrored database item is missing. or …​ it must end with /Files/LandingZone. and adds Copy it from the Home page of the mirrored database. Fix: paste the whole URL;

Put an ID that OneLake does not accept in the URL, such as the all-zero GUID. The notification Data Lake Storage reads Status code 400, InvalidRequestUri. Fix: check both IDs in the URL.