Junos OS Interfaces Command Reference - Juniper Networks

CHAPTER 25
Discard Interface Operational Mode
Commands
Table 161 on page 927 summarizes the command-line interface (CLI) command that you
can use to monitor and troubleshoot the discard (dsc) interface.
Table 161: Discard Interface Operational Mode Commands
Task
Monitor the discard interface.
Command
show interfaces (Discard)
The discard interface is not a physical interface, but a virtual interface that discards
packets. You can configure one discard interface. The discard interface allows you to
identify the ingress point of a denial-of-service (DoS) attack. When your network is under
attack, the target host IP address is identified, and the local policy forwards attacking
packets to the discard interface. Traffic routed out of the discard interface is silently
discarded.
Copyright © 2012, Juniper Networks, Inc.
If an output filter is attached to the interface, the action specified by the filter causes the
packets to be logged or counted before the traffic is discarded. For a complete discussion
about using the discard interface to protect your network against DoS attacks, see the
Junos Policy Framework Configuration Guide.
Statistics and media displayed by the show interfaces command are not relevant for the
discard interface and always show values of 0.
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