RHEL 8/9 - Setting the hostname and IP Address

Setting the hostname

sudo hostnamectl set-hostname new_hostname

Find the NIC name

In this case it is named “ens18”.

$ nmcli device
DEVICE  TYPE      STATE      CONNECTION
ens18   ethernet  connected  ens18
lo      loopback  unmanaged  --

$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    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: ens18: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 62:bc:97:42:fd:4c brd ff:ff:ff:ff:ff:ff
    altname enp0s18
    inet 192.168.1.118/24 brd 192.168.1.255 scope global dynamic noprefixroute ens18
       valid_lft 42106sec preferred_lft 42106sec
    inet6 2600:1700:60ee:19f:60bc:97ff:fe42:fd4c/64 scope global dynamic noprefixroute
       valid_lft 1788sec preferred_lft 1788sec
    inet6 fd2d:f81:8e91:0:60bc:97ff:fe42:fd4c/64 scope global noprefixroute
       valid_lft forever preferred_lft forever
    inet6 fe80::60bc:97ff:fe42:fd4c/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

Change the IP address using nmtui

Using the “nmtui” utility”

Change the IP address using nmcli

# Change the IP address to 'manual' (static) and specify the gateway (default route)
sudo nmcli con modify 'ens18' ipv4.method manual ipv4.addresses 192.168.1.181/24 gw4 192.168.1.1

# Set the DNS
sudo nmcli con modify 'ens18' ipv4.dns 4.2.2.2

# Stop and start the interface to use the new settings. Reboot also works.
sudo nmcli con down 'ens18'
sudo nmcli con up 'ens18'

Setting the interface to DHCP is way easier using the nmtui utility.