In my previous post i have explained how to install and configure DHCP server on CentOS. Here we are going to configure the dhcp server with different/multiple subnet network.
Before making the changes in dhcp.conf file, take the backup for safer side.
[root@server.local ~]#cp /etc/dhcp/dhcpd.conf /etc/dhcp/dhcpd.conf_bak20140708
The DHCP daemon listens on all network interfaces unless otherwise specified. The following /etc/sysconfig/dhcpd example specifies that the DHCP daemon listens on the eth0 and eth1 interfaces:
DHCPDARGS="eth0 eth1";
If a system has three network interfaces cards — eth0, eth1, and eth2 — and it is only desired that the DHCP daemon listens on eth0, then only specify eth0 in /etc/sysconfig/dhcpd:
DHCPDARGS="eth0";
For example, we have two network interfaces, eth0 listens to 192.168.1.0/24 network and eth1 listens to 192.168.2.0/24 network. Then the dhcp server configuraiton should be as below settings.
option domain-name "example.com";
option domain-name-servers 192.168.1.100, 192.168.1.200
default-lease-time 600;
max-lease-time 7200;
subnet 192.168.1.0 netmask 255.255.255.0 {
option subnet-mask 255.255.255.0;
option routers 192.168.1.1;
range 192.168.1.1 192.168.1.254;
}
subnet 192.168.2.0 netmask 255.255.255.0 {
option subnet-mask 255.255.255.0;
option routers 192.168.2.1;
range 192.168.2.1 192.168.2.254;
}
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