Configuring ARP Retries
In the Dell Networking OS versions prior to 8.3.1.0, the number of ARP retries is set to five and is not
configurable. After five retries, the system backs off for 20 seconds before it sends a new request.
Beginning with the Dell Networking OS version 8.3.1.0, the number of ARP retries is configurable.
The default backoff interval remains at 20 seconds. On the MXL switch platform, using the Dell
Networking OS version 8.3.8.0 and later, the time between ARP re-send is configurable. This timer is an
exponential backoff timer. Over the specified period, the time between ARP requests increases. This
reduces the potential for the system to slow down while waiting for a multitude of ARP responses.
To set and display ARP retries, use the following commands.
• Set the number of ARP retries.
CONFIGURATION mode
arp retries number
The default is 5.
The range is from 1 to 20.
• Set the exponential timer for resending unresolved ARPs.
CONFIGURATION mode
arp backoff-time
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
IPv4 Routing 449