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The default is
30
.
The range is from 1 to 3600.
•
Display all ARP entries learned via gratuitous ARP.
EXEC Privilege mode
show arp retries
ICMP
For diagnostics, the internet control message protocol (ICMP) provides routing information to end stations by choosing the best
route (ICMP redirect messages) or determining if a router is reachable (ICMP Echo or Echo Reply).
ICMP error messages inform the router of problems in a particular packet. These messages are sent only on unicast traffic.
Configuration Tasks for ICMP
The following lists the configuration tasks for ICMP.
•
Enabling ICMP Unreachable Messages
For a complete listing of all commands related to ICMP, refer to the
Dell Networking OS Command Line Reference Guide
.
Enabling ICMP Unreachable Messages
By default, ICMP unreachable messages are disabled.
When enabled, ICMP unreachable messages are created and sent out all interfaces.
To disable and re-enable ICMP unreachable messages, use the following commands.
•
To disable ICMP unreachable messages.
INTERFACE mode
no ip unreachable
•
Set Dell Networking OS to create and send ICMP unreachable messages on the interface.
INTERFACE mode
ip unreachable
To view if ICMP unreachable messages are sent on the interface, use the
show config
command in INTERFACE mode. If it is not
listed in the
show config
command output, it is enabled. Only non-default information is displayed in the
show config
command output.
UDP Helper
User datagram protocol (UDP) helper allows you to direct the forwarding IP/UDP broadcast traffic by creating special broadcast
addresses and rewriting the destination IP address of packets to match those addresses.
Configure UDP Helper
To configure Dell Networking OS to direct UDP broadcast, enable UDP helper and specify the UDP ports for which traffic is
forwarded. See
Important Points to Remember
•
The existing
ip directed broadcast
command is rendered meaningless if you enable UDP helper on the same interface.
IPv4 Routing
413
Summary of Contents for S4048-ON
Page 1: ...Dell Configuration Guide for the S4048 ON System 9 9 0 0 ...
Page 146: ...Figure 14 BFD Three Way Handshake State Changes 146 Bidirectional Forwarding Detection BFD ...
Page 522: ...Figure 87 Configuring Interfaces for MSDP 522 Multicast Source Discovery Protocol MSDP ...
Page 523: ...Figure 88 Configuring OSPF and BGP for MSDP Multicast Source Discovery Protocol MSDP 523 ...
Page 528: ...Figure 91 MSDP Default Peer Scenario 1 528 Multicast Source Discovery Protocol MSDP ...
Page 529: ...Figure 92 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 529 ...
Page 530: ...Figure 93 MSDP Default Peer Scenario 3 530 Multicast Source Discovery Protocol MSDP ...
Page 633: ...Policy based Routing PBR 633 ...
Page 777: ...Figure 119 Single and Double Tag TPID Match Service Provider Bridging 777 ...
Page 778: ...Figure 120 Single and Double Tag First byte TPID Match 778 Service Provider Bridging ...