Warning: Validate Oplog Retention Configuration

Issue

The following warning appears on the Fivetran dashboard:

Validate Oplog Retention Configuration

Environment

Connector: MongoDB

Resolution

To resolve this issue, follow the steps below:

Increase oplog size or connection sync frequency

Choose either of the following options:

• In MongoDB, adjust your oplog size to support the required volume of data sufficiently. We recommend increasing the size to retain seven days worth of data. For more information, see step 4 of our MongoDB setup guide.

• In Fivetran, limit the volume of data processed during each sync by increasing your connection's sync frequency:

  i. In Fivetran, go to your MongoDB connection page.

  ii. Select the Setup tab.

  iii. Update the value in the Sync frequency drop-down menu.

Cause

This issue occurs when the oplog and stream cursors expire between two syncs. This may happen because the oplog size isn't sufficient to support the required volume of data.