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dhcrelay

Relaying DHCP and BOOTP requests can be provided using the dhcrelay command

Supplementary instructions

dhcrelay Command Use the dhcrelay command to provide relay DHCP and BOOTP requests from a subnet without a DHCP server to a direct connection to one or more DHCP servers in other subnets. This command is used on the DHCP relay server and supports both DHCPv4/BOOTP and DHCPv6 protocols.

grammar

dhcrelay [options] [DHCP server]

Options

-c <hop count> When forwarding packets, dhcrelay discards packets that have reached a maximum hop count. The default value is 10, the maximum value is 255
-4 Run the dhcrelay command as a DHCPv4/BOOTP relay agent. This is the default operating mode
-6 Run the dhcrelay command as a DHCPv6 relay agent
-q quiet mode
-p <port> Listen and send port. The default port of DHCPv4/BOOTP is 67, and the default port of DHCPv6 is 547
-A <length> specifies the maximum packet size sent to the DHCP server
-d forces the dhcrelay command to run as a foreground process

example

Specify the location of the DHCP server.

[root@localhost ~]# dhcrelay 192.168.0.2
Internet Systems Consortium DHCP Relay Agent4.1.1-P1
Copyright 2004-2010 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/
Listening on LPF/eth1/00:0c:29:fc:2f:ef
Sending on LPF/eth1/00:0c:29:fc:2f:ef
Listening on LPF/eth0/00:0c:27:fc:25:ec
Sending on LPF/eth0/00:0c:27:fc:25:ec
Sending on Socket/fallback