Frequently asked questions for Networking

How to see active connections and bandwidth usage on Linux

Show actual bandwidth usage and active connections using the iftop tool on Linux.

How to see errors and dropped packets on a network interface on Linux

Show the network link details using the ip command to find out if a network has errors or dropped packets on a Linux system.

How to see open ports on Linux

Show which UDP/TCP ports are opened on a Linux system, including the related process. Use the ss tool to see more details about these sockets.

How to see the default gateway on Linux

Show the network routing table to discover the default gateway used on a Linux system.

How to see the IP address of your internet connection

Show the IP address of your internet connection using the dig command.

How to see the number of open connections on Linux

Show the number of open connections using the ss command on Linux.

How to see the the network IP address of your system

Show the IP address of your system with the help of the ip command.

How to see the TTL value of a DNS record

Learn how to query the Time To Live (TTL) for a DNS record by using the dig tool.

How to see which DNS server is used

Find the active DNS server being used by reviewing the network configuration, including common commands to query this information.

How to see which process is using a port

Show which process is already opened an UDP or TCP port on Linux by using the ss command.

How to show network TCP statistics and counters

Show counters related to the TCP connections by using the nstat command. This small utility will quickly retrieve the related statistics and display them.

Show to clear the DNS cache with systemd

Learn how to inspect and clear the DNS cache when using the systemd resolver daemon.