ip-link:tldr:54f49

The command "ip link show ${ethN}" is used to display information about a specific network interface. Here is a breakdown of the command:

• "ip" refers to the command-line utility for managing and administering network interfaces and configurations in Linux.
• "link" is a subcommand that specifically deals with network links, which are the network interfaces on a system.
• "show" is an option that instructs the "ip link" command to display information about network interfaces.
• "${ethN}" is a placeholder variable representing the name of a specific Ethernet interface. The actual value for "${ethN}" must be provided when running the command.

Based on the value provided for "${ethN}", the command will show details regarding that particular network interface, such as its state (up or down), type (Ethernet, loopback, etc.), MAC address, maximum transmission unit (MTU), any associated addresses or routes, and other relevant information.