Ephemeral configuration database support for synchronous commit synchronize operations

You can configure the ephemeral database to execute commit synchronize operations using a synchronous commit model on dual Routing Engine devices or MX Series Virtual Chassis. The synchronous commit model enables you to reliably use the ephemeral database on devices that have Graceful Routing Engine switchover (GRES) or non-stop routing (NSR) enabled. To use the synchronous commit model for the ephemeral database, configure the commit-synchronize-model synchronous statement at the [edit system configuration-database ephemeral] hierarchy level.

Note: Starting in 25.4, we've changed the default commit synchronize model for the ephemeral database from the asynchronous model to the synchronous model. The synchronous model provides better assurance that the ephemeral configuration is synchronized across Routing Engines or Virtual Chassis members by processing commits synchronously. With this change, only the synchronous model supports synchronizing ephemeral data on devices that have graceful Routing Engine switchover (GRES) or nonstop active routing (NSR) enabled.