rarpd - Reverse Address Resolution Protocol (RARP) daemon
] [-b bootdir
is a daemon which responds to RARP requests. RARP is used by some
machines at boot time to discover their IP address. They provide their
Ethernet address and rarpd
responds with their IP address if it finds
it in the ethers database (either /etc/ethers
file or NIS+ lookup) and
using DNS lookup if the ethers database contains a hostname and not an IP
address. In addition, /etc/hosts
will provide further means of pairing
an IP address to a hostname, in the standard fashion.
By default rarpd
also checks if a bootable image, of a name starting with
the IP address in hexadecimal upper-case letters, is present in the TFTP boot
directory before it decides whether to respond to the RARP request. The
comparison involves exactly the first eight characters, and ignores any
additional character. A file name shorter than eight characters in length is
unsuccessful. Typically, 192.168.0.122
would correspond to an image
named like C0A8007A.SUN
The optional argument interface
restricts the daemon instance to access
only the indicated network interface. Only a single name is possible.
- Do not bind to a single interface, but listen at all
- Respond to reverse requests received as ARP-packets, in
addition to those protocol conformant requests transmitted as
RARP-packets. See the notes for the background.
- Tell the user what is going on by being verbose.
- Debugging mode. Do not detach from the tty. This also
implies verbose mode.
- Skip the check for bootable images in the TFTP boot
directory. In the absence of this switch, even if the Ethernet address is
present in the ethers database, the lack of a bootable image for the
resolved IP will make rarpd refrain from responding to requests for
this particular address.
- Accept offlink packages on the active interfaces.
- -b bootdir
- Access bootdir instead of the default
/tftpboot as the TFTP boot directory for bootable image
This daemon rarpd
obsoletes kernel rarp
daemon present in Linux
kernels up to 2.2 which was controlled by the rarp(8) command.
- Renew the internal address list, which records IPv4
addresses available at each active network interface. The restriction set
by the command line argument interface is still in effect, if in
The protocol stipulates that Reverse Requests be broadcast as RARP packets,
using a protocol number different from that in use by ARP packets. However,
there has been an obsolete practice of transmitting also Reverse Requests in
ARP packets, and some old clients may still be around that adhere to that
practice. To activate support for such obsolete client hosts, the switch
must be applied. Observe, however, that only ARP-packaged
ARPOP_RREQUEST messages are added to the servers responsabilities with the use
of this option, and that the replies to these will be sent as ARP-packaged
- Text data base of ethernet to host pairs.
- Text lookup table of host names.
- Name resolver configuration.
- Default boot directory.
- Typical name of a boot image. It is a file or a directory.
The IPv4 address is translated as eight upper-case, hexadecimal digits in
the mandatory part HEXADDR. Optionally, the name may be extended
with an arbitrary suffix.
ethers(5), hosts(5), nsswitch.conf(5)
Alexey Kuznetsov, <email@example.com>
Jakub Jelinek, <firstname.lastname@example.org>