Which statements are true about graceful Routing Engines switchover (GRES)?

When it comes to graceful Routing Engines switchover (GRES), one of the crucial aspects is the synchronization of configuration between the primary and backup Routing Engines. This ensures seamless failover and allows for continuous operation without disruption. When configurations are not synchronized, inconsistencies may lead to unexpected behaviors or failures during a switchover.

Synchronizing configurations involves ensuring that both Routing Engines have the same routing policies, protocols, and interfaces configured. It is vital for maintaining state information, routing tables, and overall system performance during the transition from one Routing Engine to another, particularly in high-availability scenarios.

This emphasis on synchronized configurations supports the principle of high availability, allowing the backup Routing Engine to take over with minimal service interruption if the primary Routing Engine fails or needs to be taken down for maintenance.