linuxexpert-practice-labs/labs/rhcsa/8-1-ip-addresses

RHCSA 8.1: IPv4 and IPv6 addresses

Static IPv4 and IPv6 addresses, a gateway and a DNS server on a spare interface with nmcli, a second address, and the same again with nmtui.

Before you start

The lab gives this VM a spare network interface, eth1, cabled to a small lab network, 192.168.50.0/24, where a machine answers at 192.168.50.1 (and fd00:50::1). It comes back at every boot. eth1 has no profile yet. Your SSH connection doesn't use it, so leave the main interface alone.

A gateway and DNS server on eth1 rank below the main interface's (the lab sets that up in /etc/NetworkManager/conf.d/), so the VM keeps its own way out. Profiles come and go in task 3, so the lab runs a small service, le-lab-watch, that notes the profiles for eth1 for the check.

Tasks

1. Give eth1 the static IPv4 address 192.168.50.10/24, gateway 192.168.50.1, DNS server 192.168.50.1, and the IPv6 address fd00:50::10/64, all persistent, in a profile made with nmcli.
2. Add a second IPv4 address, 192.168.50.11/24, to the same profile without removing the first.
3. Delete that profile with nmcli connection delete, and do tasks 1 and 2 again with nmtui on a fresh profile.

Hints

• nmcli connection add type ethernet ifname eth1 con-name eth1 ipv4.method manual ipv4.addresses ... ipv4.gateway ... ipv4.dns ... ipv6.method manual ipv6.addresses ....
• nmcli connection modify NAME +ipv4.addresses ..., then nmcli connection up NAME; nmcli -g ipv4.addresses connection show NAME.
• In nmtui, "Edit a connection", "Add", "Ethernet", device eth1; set IPv4 and IPv6 to "Manual".
• ip -br addr show eth1, ip route, cat /etc/resolv.conf, ping 192.168.50.1.