The
utility services Reverse ARP requests on the Ethernet connected to
interface
Upon receiving a request,
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
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,
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,
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 permits
to selectively respond to RARP requests, but use an alternate directory
for IP checking.
An -nosplit
An Craig Leres Aq leres@ee.lbl.gov
and
An Steven McCanne Aq mccanne@ee.lbl.gov .
Lawrence Berkeley Laboratory, University of California, Berkeley, CA.
BUGS
The
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.conf5
to read
/etc/hosts
first.
