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 kernel.  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 consists of an IP address, an Ethernet address and the status of the entry.  Entries may be invalid, permanent or temporary.  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)

Plan 9  —  January 03, 1993