ping
Ping is one of the most basic tools for testing connectivity to other hosts. It sends an Internet Control Message Protocol (ICMP) echo request to a host and listens for the reply. If a reply is received, it will display the time it took and the time to live (TTL) left. Ping has many options for setting attributes of the request, like the maximum TTL, IPv4/IPv6, and the number of requests to send. Ping is useful in troubleshooting connectivity with other devices. If a reply is not received, you will receive a timeout message, which could indicate connectivity issues, firewall issues, or both issues with the other device. In addition, due to the time to get a response, the latency between two devices can be measured, enabling a network engineer to troubleshoot performance problems or a network architect to determine where to place devices to minimize response time to other systems and users.