Creating static arp entries, Changing the arp timer, Changing the arp pending retry timer – Brocade Multi-Service IronWare Switching Configuration Guide (Supporting R05.6.00) User Manual
Page 783
Multi-Service IronWare Switching Configuration Guide
753
53-1003036-02
Configuring ARP parameters
19
Creating static ARP entries
The Brocade device has a static ARP table, in addition to the regular ARP cache. The static ARP
table contains entries that you configure.
Static entries are useful in cases where you want to pre-configure an entry for a device that is not
connected to the Brocade device, or you want to prevent a particular entry from aging out. The
software removes a dynamic entry from the ARP cache if the ARP aging interval expires before the
entry is refreshed. Static entries do not age out, regardless of whether the device receives an ARP
request from the device that has the entry’s address.
You can increase the number of configurable static ARP entries. Refer to
To display the ARP cache and static ARP table, refer to the following:
•
To display the ARP table, refer to
•
To display the static ARP table, refer to
“Displaying the static ARP table”
•
To create a static ARP entry for a static MAC entry, refer to
Changing the ARP timer
When an entry is initially added to the ARP table, it is listed as “Pending.” When it is in this state, a
series of ARP requests are made to determine if it is a valid entry. If the first attempt succeeds, the
status of the entry is changed to “dynamic.” It is then subject to the normal rules for dynamic
entries. If three attempts fail, the entry is removed from the table.
The ARP timer determines the amount of time that elapses after the ARP request is sent before
determining that the request has failed.The arp-timer command allows you change the length of
the ARP timer as shown in the following.
Brocade(config)# ip arp-timer 12
Syntax: [no] ip arp-timer timer-value
The timer-value variable has now been changed so that you are able to enter a value between 1
and 500. Each increment represents 100 ms. Consequently, the minimum value of 1 equals 100
ms.
The default value is 10 which equals 1 sec.
This value can be used to adjust how frequently an ARP request is sent out for a pending ARP entry.
Changing the ARP pending retry timer
The ARP Pending Retry Timer for Brocade device will send out three ARP request packets for the
configured period until ARP is resolved to prevent large amounts of ARP requests from flooding the
network during network host scanning activity. The ARP Pending Retry Timer is configurable
depending upon the requirements of your system configurations.
The arp-pending-retry-timer command allows you to change the length of the ARP pending retry
timer as shown in the following.
Brocade(config)# ip arp-pending-retry-timer 120
Syntax: [no] ip arp-pending-retry-timer timer-value