How Do I set up DHCP client for one network interface to get IP Address from a DHcP server under CentOS 7 or RHEL 7 linux? How Do I modify the BOOTPROTO setting from Static or “Nome” to “DHcP” so that the network interface will get the ipaddress via a DHCP server. you will see that how to setup your centos 7 system as a DHCP Client.
You firstly need to find which network interface you want to setup its as DHCP client, then edit its configuration file and changing the value of BOOTPROTO from “Static” or “None” To “DHCP“. Let’s start to setup DHcP Client through the following steps.
CentOS 7 Setup DHCP client
Step1# issue the following command to find the network interface name that you would like to set its as DHcP client, type:
ifconfig
or
ip addr
outputs:
[root@devops network-scripts]# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 08:00:27:ea:92:ea brd ff:ff:ff:ff:ff:ff inet 10.0.2.15/24 brd 10.0.2.255 scope global dynamic enp0s3 valid_lft 69691sec preferred_lft 69691sec inet 10.0.2.16/24 brd 10.0.2.255 scope global secondary enp0s3:0 valid_lft forever preferred_lft forever inet 10.0.2.17/24 brd 10.0.2.255 scope global secondary enp0s3:1 valid_lft forever preferred_lft forever inet6 fe80::a00:27ff:feea:92ea/64 scope link valid_lft forever preferred_lft forever
In the below steps ,we will set “enp0s3” network interface as DHCP client.
Step2# backup existing static netowrk interface configruation file, issue the following command:
cp /etc/sysconfig/network-scripts/ifcfg-enp0s3 /etc/sysconfig/network-scripts/ifcfg-enp0s3.bak
Step3# edit “/etc/sysconfig/network-scripts/ifcfg-enp0s3” configuration file via “vim” command:
vim /etc/sysconfig/network-scripts/ifcfg-enp0s3
The following content is current configuration:
HWADDR=08:00:27:32:D1:01 TYPE=Ethernet BOOTPROTO=static NAME=enp0s3 IPADDR=10.0.2.15 NETMASK=255.255.255.0 DEFROUTE=yes PEERDNS=yes PEERROUTES=yes IPV4_FAILURE_FATAL=no IPV6INIT=yes IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_PEERDNS=yes IPV6_PEERROUTES=yes IPV6_FAILURE_FATAL=no UUID=8d307f87-e025-46cc-87d8-4c4235375768 ONBOOT=no
Replace the above content with the following configuration:
HWADDR=08:00:27:32:D1:01 TYPE=Ethernet BOOTPROTO=dhcp #=====>change this, removing Ip address and netmask DEFROUTE=yes PEERDNS=yes PEERROUTES=yes IPV4_FAILURE_FATAL=no IPV6INIT=yes IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_PEERDNS=yes IPV6_PEERROUTES=yes IPV6_FAILURE_FATAL=no NAME=enp0s3 UUID=8d307f87-e025-46cc-87d8-4c4235375768 ONBOOT=no
Save and close above configuration file.
Step4# restart network service by running the following command so that the changes can take effect,type:
systemctl restart network.service