Which command helps in monitoring system performance and interface status in Junos?

The command that effectively aids in monitoring system performance and interface status in Junos is the one that presents detailed information regarding the status of network interfaces. This command provides insights into various performance metrics for each interface, including packet counts, error rates, and the operational status of the interfaces. By utilizing this command, network administrators can quickly determine whether interfaces are up or down, monitor traffic statistics, and diagnose potential issues that may affect network performance.

This command is a fundamental tool for any network specialist working with Junos, as it directly relates to the health and efficiency of the network interfaces, which are crucial for maintaining optimal system performance. The insights gleaned from this command can guide troubleshooting efforts and help in the overall management of network resources. Other options may provide different types of information or focus on specific aspects that do not encompass the comprehensive monitoring of both system performance and interface status in a straightforward manner.