enable icmp port-unreachables

enable icmp port-unreachables {vlan name}


Enables the generation of ICMP (Internet Control Message Protocol) port unreachable messages on one or all VLAN (Virtual LAN)s.

Syntax Description

name Specifies a VLAN name.



Usage Guidelines

Enables the generation of ICMP port unreachable messages (type 3, code 3) when a TCP or UDP request is made to the switch and no application is waiting for the request, or when an access policy denies the request. If a VLAN is not specified, the command applies to all IP interfaces.

This command only affects the generation of certain ICMP packets. Filtering of ICMP packets usually forwarded by the switch is controlled by the access-list commands.


The following command enables ICMP port unreachable messages on VLAN "accounting":

enable icmp port-unreachables vlan accounting


This command was first available in ExtremeXOS 10.1.

Platform Availability

This command is available on the Summit X450-G2, X460-G2, X670-G2, X770, and ExtremeSwitching X440-G2, X620, X690, X870 series switches.