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Commands to Display a Traffic Black-Hole Condition Due to a Degraded Fabric


The Juniper Networks T Series Core Routers and TX Matrix support various CLI commands to display unreachable destinations present because of a degraded fabric condition. Junos® OS provides two different modes as follows:

  • Operational mode: Displays the current status of the device. Typically, you enter commands to monitor and troubleshoot Junos OS, devices, and associated features.

  • Configuration mode: In configuration mode, you enter the statements to define all properties of Junos OS, including interfaces, general routing information, routing protocols, user access, and system and hardware properties.

For this example, the following operational mode commands are used: