Which tool can be used to configure virtual network interfaces?

The correct choice is that all the mentioned tools—ip, ifup, and nmcli—can indeed be used to configure virtual network interfaces.

The tool "ip" is a powerful command used to manage network interfaces and routing in Linux. It allows you to create, delete, or modify virtual interfaces, making it versatile for network configurations, especially in environments where you may need to create logical interfaces or aliases.

The "ifup" command is traditionally used in conjunction with the configuration files in the system, particularly in Debian-based systems, to bring up network interfaces defined in the interfaces file. This includes virtual interfaces, allowing you to manage them easily as part of the network configuration process.

"nmcli" is the command-line interface for NetworkManager, which is a tool designed for managing network connections interactively and programmatically. It can create and manage both physical and virtual network interfaces, including bridges, bonds, and VLANs.

Since all three tools support the configuration and management of virtual network interfaces, the answer reflects the breadth of tools available in Linux for this purpose.