ARP(3) ARP(3)
NAME
arp - Internet Address Resolution Protocol
SYNOPSIS
bind -a #a /net/arp
/net/arp/ctl
/net/arp/data
/net/arp/stats
DESCRIPTION
The arp device provides the means by which the kernel
resolves IP addresses into Ethernet addresses. A cache is
maintained by the arp device to speed the process.
The ctl file controls the ARP cache maintained by the ker-
nel. The flush control message invalidates all entries in
the cache. The delete ipaddr control message invalidates a
single cache entry.
The data file provides two interfaces. The first open of
the data file connects the arpd server to the kernel ARP
cache (see ipconfig(8)). Arpd writes the results of address
resolution requests from the kernel back into the data file
to prime the cache. Subsequent opens of the data file allow
the contents of the cache to be read. Each cache entry con-
sists of an IP address, an Ethernet address and the status
of the entry. Entries may be invalid, permanent or tempo-
rary. Permanent entries will never be aged from the cache.
Temporary entries may be replaced by new addresses entered
by the ARP server.
The file stats reports the cache performance.
SEE ALSO
ip(3), ipconfig(8)
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