NAME
dhcp-helper - A DHCP/BOOTP relay agent.
SYNOPSIS
dhcp-helper [OPTION]...
DESCRIPTION
dhcp-helper is a DHCP and BOOTP relay agent. It listens for DHCP and
BOOTP broadcasts on directly connected subnets and relays them to DHCP
or BOOTP servers elsewhere. It also relays replies from the remote
servers back to partially configured hosts. Once hosts are fully
configured they can communicate directly with their servers and no
longer need the services of a relay.
OPTIONS
The only required option is at least one DHCP server to relay to. The
simplest way to configure dhcp-helper on a router is just to give the
interface to the network containing the DHCP server with a -b option.
All the other interfaces present on the machine will then accept DHCP
requests. On a machine which does not have an interface on the network
containing the DHCP server, use a -s option instead.
-s <server>
Specify a DHCP or BOOTP server to relay to. The server may be
given as a machine name or dotted-quad IP address. More than one
server may be specified.
-b <interface>
Relay to a DHCP or BOOTP server using broadcast via <interface>.
This eliminates the need to give a server address. <interface>
is automatically added to the list of interfaces which will not
receive DHCP requests.
-i <interface>
Specify which local interfaces to listen on for DHCP/BOOTP
broadcasts. If no -i flags are given all interfaces are used
except those specified by -e flags and those specified by -b
flags.
-e <interface>
Specify which local interfaces to exclude.
-p Use alternative ports (1067/1068) for the DHCP client and
server.
-v Report the software release version and copyright information.
-d Debug mode, do not change UID, write a pid-file or go into the
background.
-r <file>
Specify an alternate path for dhcp-helper to record its process-
id in. Normally /var/run/dhcp-helper.pid.
-u <username>
Specify the userid to which dhcp-helper will change after
startup. The daemon must normally be started as root, but it
will drop root priviledges after startup by changing id to
another user. Normally this user is "nobody" but that can be
over-ridden with this switch.
NOTES
Dhcp-helper requires a 2.2 or later Linux kernel. The "Linux packet
filter" and "packet socket" facilities are not required, which is the
chief advantage of this software over the ISC DHCP relay daemon.
AUTHOR
This manual page was written by Simon Kelley <simon@thekelleys.org.uk>.