NAME
rarpd
—
reverse ARP daemon
SYNOPSIS
rarpd |
-a [-dfsv ]
[-t directory] |
rarpd |
[-dfsv ] [-t
directory] interface |
DESCRIPTION
Therarpd
utility services Reverse ARP requests on the
Ethernet connected to interface. Upon receiving a
request, rarpd
maps the target hardware address to an
IP address via its name, which must be present in both the
ethers(5) and
hosts(5) databases. If a host does not exist in both databases, the
translation cannot proceed and a reply will not be sent.
By default, a request is honored only if the server
(i.e., the host that rarpd
is running on) can
"boot" the target; that is, a file or directory matching the glob
/tftpboot/ipaddr* exists, where
ipaddr is the
target IP address in hex. For example, the IP address 204.216.27.18 will be
replied to if any of /tftpboot/CCD81B12,
/tftpboot/CCD81B12.SUN3, or
/tftpboot/CCD81B12-boot exist. This requirement can
be overridden with the -s
flag (see below).
In normal operation, rarpd
forks a copy of
itself and runs in the background. Anomalies and errors are reported via
syslog(3).
The following options are available:
-a
- Listen on all the Ethernets attached to the system. If
-a
is omitted, an interface must be specified. -d
- If
-f
is also specified,rarpd
logs messages to stdout and stderr instead of via syslog(3). -f
- Run in the foreground.
-s
- Supply a response to any RARP request for which an ethernet to IP address mapping exists; do not depend on the existence of /tftpboot/ipaddr*.
-t
- Supply an alternate tftp root directory to
/tftpboot, similar to the
-s
option of tftpd(8). This permitsrarpd
to selectively respond to RARP requests, but use an alternate directory for IP checking. -v
- Enable verbose syslogging.
FILES
- /etc/ethers
- /etc/hosts
- /tftpboot
SEE ALSO
Finlayson, R., Mann, T., Mogul, J.C., and Theimer, M., RFC 903: Reverse Address Resolution Protocol, June 1984, 4 p.
AUTHORS
Craig Leres <leres@ee.lbl.gov> and Steven McCanne <mccanne@ee.lbl.gov>. Lawrence Berkeley Laboratory, University of California, Berkeley, CA.
BUGS
The rarpd
utility can depend on the DNS to
resolve the name discovered from /etc/ethers. If
this name is not in the DNS but is in /etc/hosts,
the DNS lookup can cause a delayed RARP response, so in this situation it is
recommended to configure
nsswitch.conf(5) to read /etc/hosts
first.