476 | IPv4 Addressingw w w . d e l l . c o m | s u p p o r t . d e l l . c o m Enable ICMP unreachable messagesBy default, ICMP unreachable messages are disabled. When enabled ICMP unreachable messages arecreated and sent out all interfaces. To disable ICMP unreachable messages, use the no ip unreachablecommand.To reenable the creation of ICMP unreachable messages on the interface, use the following command inthe INTERFACE mode:To view if ICMP unreachable messages are sent on the interface, use the show config command in theINTERFACE mode. If it is not listed in the show config command output, it is enabled. Only nondefaultinformation is displayed in the show config command output.Enable ICMP redirectsEnable ICMP redirects is supported on e platformBy default, ICMP redirect messages are disabled. When enabled, ICMP redirect messages are created andsent out all interfaces. To disable ICMP redirect messages, use the no ip redirect command.To reenable the creation of ICMP redirect messages on the interface, use the following command in theINTERFACE mode:To view if ICMP redirect messages are sent on the interface, use the show config command in theINTERFACE mode. If it is not listed in the show config command output, it is enabled. Only nondefaultinformation is displayed in the show config command output.UDP HelperUDP helper allows you to direct the forwarding IP/UDP broadcast traffic by creating special broadcastaddresses and rewriting the destination IP address of packets to match those addresses. Configurationsusing this feature are described in the section Configurations Using UDP Helper on page 478.Command Syntax Command Mode Purposeip unreachable INTERFACE Set FTOS to create and send ICMP unreachablemessages on the interface.Command Syntax Command Mode Purposeip redirect INTERFACE Set FTOS to create and send ICMP redirect messages onthe interface.
