nftables
ip
Show / manipulate routing, devices, policy routing and tunnels.
Some subcommands such as ip address have their own usage documentation.
More information: https://www.man7.org/linux/man-pages/man8/ip.8.html.
List interfaces with detailed info:
ip address
List interfaces with brief network layer info:
ip -brief address
List interfaces with brief link layer info:
ip -brief link
Display the routing table:
ip route
Show neighbors (ARP table):
ip neighbour
Make an interface up/down:
ip link set interface up/down
Add/Delete an IP address to an interface:
ip addr add/del ip/mask dev interface
Add a default route:
ip route add default via ip dev interface