Configuring Arp - Novell NETWARE 6-DOCUMENTATION Manual

Configuring ARP

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4
Press Esc to return to the Internetworking Configuration menu.
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If you want these changes to take effect immediately, select Reinitialize
System > Yes.
IP routers and end nodes use ARP to determine the physical address of a node
to which they want to send a packet. ARP is enabled by default. For one node
to send a packet to another, the sending node must know the physical address
of the destination node. The sending node, knowing only the destination IP
address, first checks its ARP table for an entry that maps the destination IP
address to the destination physical address. If the sending node finds the entry,
it inserts the physical address into the packet and sends it. If the sending node
does not find the entry in its ARP table, it broadcasts an ARP address request
to the network. The destination node replies to the request with its own
physical address, which the sending node uses to send the packet and adds to
its ARP table for future use.
ARP Cache Update Timeout is the time period (in seconds) for an entry to be
removed from the ARP table, if the entry has not been updated. This value can
be set only for a primary interface, and if ARP Timer is enabled. ARP Timer
is disabled by default. For best performance, set the ARP Cache Update
timeout value to be greater than or equal to the value of ARP Cache Stale
Timeout.
The valid range of values for ARP Cache Update Timeout is from 240 to
14400 seconds. Default value is 300 seconds.
ARP Cache Stale Timeout is the time period (in seconds) for an entry to be
removed from the ARP table, if the entry has not been used for some time. If
multihoming is enabled then we can set this value for a primary IP interface if
they are grouped for load balancing and fault tolerance. In all other cases this
can be set on all IP interfaces. ARP Timer is disabled by default. For best
performance, set the ARP Cache Stale Timeout value to be lesser than or equal
to the value of ARP Cache Update Timeout.
The valid range of values for ARP Cache Stale Timeout is from 240 to 14400
seconds. Default value is 300 seconds.
An IP router uses Proxy ARP when devices attached to one of its interfaces do
not support IP subnetting and are unaware that they must go through the router
to reach devices on other subnets of the same IP network. A router using Proxy
ARP replies to ARP requests intended for devices on other subnets, but does