Configuring Network Interfaces with ip link command

Configuring Low-Level Options

• The ip link command is used to configure low-level interface or protocol settings, such as VLANs, ARP, or MTUs, or disabling an interface.
• ip link can be used to disable or enable an interface, similar to ifconfig.
• Example of disabling an interface: ip link set dev enp0s8 down
• Example of enabling an interface: ifconfig enp0s8 up

Adjusting an Interface's MTU

• ip link or ifconfig can be used to adjust an interface's MTU.
• Example of setting MTU using ip link: ip link set enp0s8 mtu 2000
• Example of setting MTU using ifconfig: ifconfig enp0s3 mtu 1500

The Routing Table

• The commands route, netstat -r, and ip route can be used to view the routing table.
• route or ip route must be used to modify the routing table.
• The routing table shows the destination, gateway, interface, protocol, scope, metric, and IPv6 route preference.

Managing Routes

• Routes can be managed using route or ip route.
• Example of adding a route using route: not shown in the text.
• Example of removing a route using route: not shown in the text.

ip Command

• The ip command is a modern and versatile utility used to configure network interfaces and review their states.

ifconfig Command

• The ifconfig command is a legacy utility used to configure network interfaces and review their states.

netstat Command

• The netstat command is a legacy command used to view current network connections and route information.

route Command

• The route command is a legacy command used to view or modify a system's routing table.

ip Route Output

• The output of ip route and ip -6 route shows the destination, optional address followed by interface, routing protocol, scope, metric, and IPv6 route preference.

Routing Table Columns

• The Ref column shows the reference count, or number of uses of a route.
• The Use column shows the number of lookups for a route.
• The MSS column shows the maximum segment size for TCP connections over that route.
• The Window column shows the default TCP window size.
• The irtt column shows the round trip time for packets on this route.

Learn how to use the ip link command to configure low-level interface or protocol settings such as VLANs, ARP, or MTUs, or disabling an interface.