Oplog Progress File

The oplog progress file keeps track of the latest oplog entry seen for each replica set to which Mongo Connector is connected.

Format

The exact format of this file depends on MongoDB's toplogy. For a single replica set, the format is:

["oplog name", timestamp]

For a sharded cluster, there is one such entry for each replica set shard:

[["oplog 1 name", timestamp 1], ["oplog 2 name", timestamp 2], ...]

Creation and Update

The oplog progress file is created as the final step of Mongo Connector's initialization and happens with or without a collection dump. The progress file is updated thereafter at the following times:

// TODO