To enable nonstop active routing (NSR), which two commands must be used?

To enable nonstop active routing (NSR) in a Junos environment, it is crucial to understand the functions that NSR serves in maintaining routing protocols during a control plane failover. One of the key requirements for enabling NSR is setting the routing options specifically for nonstop routing.

Using the command that sets routing-options nonstop-routing is essential as it directly enables NSR. This option ensures that the router maintains the routing information in the routing table even if a routing protocol is in the process of restarting. With this configuration, the router can seamlessly continue to forward packets without disruption.

In conjunction with this command, it's common to utilize another command related to graceful restart to ensure compatibility and to enhance the overall stability of routing protocols during a switchover. However, the exact combination that is necessary for NSR activation specifically hinges on enabling nonstop routing through the aforementioned command.

The interplay of these commands in NSR is critical, as enabling nonstop routing is the foundational step for achieving the high availability that NSR provides, allowing for minimal interruption of service.