diff options
| -rw-r--r-- | man/en_US/arp.8 | 159 |
1 files changed, 97 insertions, 62 deletions
diff --git a/man/en_US/arp.8 b/man/en_US/arp.8 index 3709cf6..4d20ed3 100644 --- a/man/en_US/arp.8 +++ b/man/en_US/arp.8 @@ -1,56 +1,111 @@ -.TH ARP 8 "2005-05-16" "net-tools" "Linux Programmer's Manual" +.TH ARP 8 "2007-12-01" "net-tools" "Linux Programmer's Manual" .SH NAME arp \- manipulate the system ARP cache .SH SYNOPSIS .B arp .RB [ \-vn ] -.RB [ "\-H type" ] -.RB [ "-i if" ] -.B -a -.RB [ hostname ] +.RB [ \-H +.IR type ] +.RB [ \-i +.IR if ] +.RB [ \-a ] +.RI [ hostname ] .PP .B arp .RB [ \-v ] -.RB [ "\-i if" ] -.B "\-d hostname" +.RB [ \-i +.IR if ] +.B \-d +.I hostname .RB [ pub ] .PP .B arp .RB [ \-v ] -.RB [ "\-H type" ] -.RB [ "\-i if" ] -.B -s hostname hw_addr +.RB [ \-H +.IR type ] +.RB [ \-i +.IR if ] +.B \-s +.I hostname hw_addr .RB [ temp ] .PP .B arp .RB [ \-v ] -.RB [ "\-H type" ] -.RB [ "\-i if" ] -.B -s hostname hw_addr -.RB [ "netmask nm" ] +.RB [ \-H +.IR type ] +.RB [ \-i +.IR if ] +.B \-s +.I hostname hw_addr +.RB [ netmask +.IR nm ] .B pub .PP .B arp .RB [ \-v ] -.RB [ "\-H type" ] -.RB [ "\-i if" ] -.B -Ds hostname ifa -.RB [ "netmask nm" ] +.RB [ \-H +.IR type ] +.RB [ \-i +.IR if ] +.B \-Ds +.I hostname +.I ifname +.RB [ netmask +.IR nm ] .B pub .PP .B arp .RB [ \-vnD ] -.RB [ "\-H type" ] -.RB [ "-i if" ] -.B -f [filename] +.RB [ \-H +.IR type ] +.RB [ \-i +.IR if ] +.B \-f +.RI [ filename ] .SH DESCRIPTION .B Arp -manipulates the kernel's ARP cache in various ways. The primary options -are clearing an address mapping entry and manually setting up one. For -debugging purposes, the +manipulates or displays the kernel's IPv4 network neighbour cache. It can add +entries to the table, delete one or display the current content. + +.B ARP +stands for Address Resolution Protocol, which is used to find the media +access control address of a network neighbour for a given IPv4 Address. +.SH MODES .B arp -program also allows a complete dump of the ARP cache. +with no mode specifier will print the current content of the table. It is +possible to limit the number of entries printed, by specifying an hardware +address type, interface name or host address. + +.B arp -d +.I address +will delete a ARP table entry. Root or netadmin priveledge is required to do +this. The entry is found by IP address. If a hostname is given, it will be +resolved before looking up the entry in the ARP table. + +.B arp -s +.I address hw_addr +is used to set up a new table entry. The format of the +.I hw_addr +parameter is dependent on the hardware class, but for most classes one can +assume that the usual presentation can be used. For the Ethernet class, +this is 6 bytes in hexadecimal, separated by colons. When adding proxy arp +entries (that is those with the +.BR pub lish +flag set a +.B netmask +may be specified to proxy arp for entire subnets. This is not good +practice, but is supported by older kernels because it can be +useful. If the +.B temp +flag is not supplied entries will be permanent stored into the ARP +cache. To simplyfy setting up entries for one of your own network interfaces, you can use the +.B "arp \-Ds" +.I address ifname +form. In that case the hardware address is taken from the interface with the +specified name. + +.br .SH OPTIONS .TP .B "\-v, \-\-verbose" @@ -76,21 +131,13 @@ Other values might include network technologies such as and .RB "NET/ROM (" netrom ")." .TP -.B "\-a [hostname], \-\-display [hostname]" -Shows the entries of the specified hosts. If the -.B hostname -parameter is not used, -.B all -entries will be displayed. -.TP -.B "\-d hostname, \-\-delete hostname" -Remove any entry for the specified host. This can be used if the -indicated host is brought down, for example. +.B \-a +Use alternate BSD style output format (with no fixed columns). .TP .B "\-D, \-\-use-device" -Use the interface -.BR ifa "'s" -hardware address. +Instead of a hw_addr, the given argument is the name of an interface. +.B arp +will use the MAC address of that interface for the table entry. This is usually the best option to set up a proxy ARP entry to yourself. .TP .B "\-i If, \-\-device If" Select an interface. When dumping the ARP cache only entries matching @@ -106,27 +153,6 @@ be answered. .B NOTE: This has to be different from the interface to which the IP datagrams will be routed. -.TP -.B "\-s hostname hw_addr, \-\-set hostname" -Manually create an ARP address mapping entry for host -.B hostname -with hardware address set to -.B hw_addr -. The format of the hardware address is dependent on the hardware -class, but for most classes one can assume that the usual presentation -can be used. For the Ethernet class, this is 6 bytes in hexadecimal, -separated by colons. When adding proxy arp entries (that is those with -the -.BR pub lish -flag set a -.B netmask -may be specified to proxy arp for entire subnets. This is not good -practice, but is supported by older kernels because it can be -useful. If the -.B temp -flag is not supplied entries will be permanent stored into the ARP -cache. -.br .B NOTE: As of kernel 2.2.0 it is no longer possible to set an ARP entry for an entire subnet. Linux instead does automagic proxy arp when a route @@ -170,8 +196,18 @@ flag. Permanent entries are marked with and published entries have the .B P flag. +.SH EXSAMPLES +.B /usr/sbin/arp -i eth0 -Ds 10.0.0.2 eth1 pub + +This will answer ARP requests for 10.0.0.2 on eth0 with the MAC address for +eth1. + +.B /usr/sbin/arp -i eth1 -d 10.0.0.1 + +Delete the ARP table entry for 10.0.0.1 on interface eth1. This will match +published proxy ARP entries and permanent entries. .SH FILES -.I /proc/net/arp, +.I /proc/net/arp .br .I /etc/networks .br @@ -181,5 +217,4 @@ flag. .SH SEE ALSO rarp(8), route(8), ifconfig(8), netstat(8) .SH AUTHORS -Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> with a lot of improvements -from net-tools Maintainer Bernd Eckenfels <net-tools@lina.inka.de>. +Fred N. van Kempen <waltje@uwalt.nl.mugnet.org>, Bernd Eckenfels <net-tools@lina.inka.de>. |