Procedure to change DNS ip address in RHEL

1. Edit the /etc/resolv.conf file with an editor, such as nano or vim in RHEL: sudo vim /etc/resolv.conf
2. Set the name servers (DNS IP) that you want to use on RHEL : nameserver 192.168.2.254
3. Save and close the file in RHEL
4. Test new settings

How to see the current DNS settings in RHEL

Type the following cat command:
cat /etc/resolv.conf

RHEL change DNS ip address

Type the following vim command:
$ sudo vim /etc/resolv.conf
OR
# vim /etc/resolv.conf
Edit/update nameserver entry as follows (you can set maximum 3 nameserver IP address):

## Change DNS settings on RHEL (Red Hat Enterprise Linux) ##
nameserver 192.168.2.254
nameserver 192.168.2.18

Test it using the ping command or host command/dig command:
ping -c 4 www.nixcraft.com
host www.nixcraft.com
dig www.cyberciti.biz

How to change DNS settings on RHEL using Network Manager

Simply run the following nmcli command to connection names:
$ sudo nmcli connection
To set up DNS IP address to 192.168.2.254 and 192.168.2.18, run:
sudo nmcli con mod {connectionNameHere} ipv4.dns "192.168.2.254 192.168.2.18"
In this example just set up DNS IP to 192.168.2.254 from the CLI on RHEL:
sudo nmcli con mod eth0 ipv4.dns "192.168.2.254"
Reload new DNS settings by running any one of the following command:
sudo systemctl restart NetworkManager.service
OR
sudo nmcli connection reload
Verify it by using the grep command and cat command and host command:
cat /etc/resolv.conf
grep DNS /etc/sysconfig/network-scripts/ifcfg-Ethernet_connection_1
host www.cyberciti.biz

Conclusion

This page described how to change your RHEL server’s DNS IP settings using the CLI.