DHCRELAY(8) OpenBSD System Manager's Manual DHCRELAY(8)NAMEdhcrelay - Dynamic Host Configuration Protocol relay agent
SYNOPSISdhcrelay [-do] -i interface server1 [... serverN]
DESCRIPTION
The dhcrelay utility provides a means for relaying DHCP and BOOTP
requests from a subnet to which no DHCP server is directly connected to
one or more DHCP servers on other subnets.
dhcrelay listens for DHCP requests on a given interface. When a query is
received, dhcrelay forwards it to the list of DHCP servers specified on
the command line. When a reply is received, it is broadcast or unicast
on the network from whence the original request came.
The name of at least one DHCP server to which DHCP and BOOTP requests
should be relayed, as well as the name of the network interface that
dhcrelay should attempt to configure, must be specified on the command
line.
dhcrelay supports relaying of DHCP traffic to configure IPsec tunnel mode
clients when listening on the enc(4) interface. The DHCP server has to
support RFC 3046 to echo back the relay agent information to allow
stateless DHCP reply to IPsec tunnel mapping.
The options are as follows:
-ddhcrelay normally runs in the foreground until it has configured
an interface, and then reverts to running in the background.
This option forces dhcrelay to always run as a foreground
process.
-i interface
The name of the network interface that dhcrelay should attempt to
configure. At least one IPv4 address has to be configured on
this interface.
-o Add the relay agent information option. By default, this is only
enabled for the enc(4) interface.
SEE ALSOdhclient(8), dhcpd(8)
RFC 2132, RFC 2131, RFC 3046, RFC 3456
AUTHORSdhcrelay was written by Ted Lemon <mellon@fugue.com>.
The current implementation was reworked by Henning Brauer
<henning@openbsd.org>.
BUGS
Relayed DHCP traffic could actually safely be protected by IPsec but,
like dhcpd(8) and dhclient(8), dhcrelay will bypass IPsec for all its
traffic.
OpenBSD 4.9 October 8, 2010 OpenBSD 4.9