Testing the connectivity between machines are useful to see if the firewall is open for whatever traffic that is needed. Specifically in enterprise networks and services that is communicating with a service in another enterprise network. In cases like that, there might be necessary to open up the firewall for the service in both ends.
Telnet is my goto tool whenever I need to check if there is connectivity from one machine to another machine on a specific port.
C:\> telnet google.com 443
The command is simple and the test goes fast. In the example above, I am testing if there is possible to connect to
google.com on port 443.
google.comcan be changed to whatever domain or machinename that need to be checked.
Sometimes I do not have the telnet client available and enabling this feature in Windows Server is easy, but it requires a restart of the server when done. There is a Powershell command that can be used and works great. The command is quite powerful and can be used to a lot more.
PS C:\> Test-NetConnection -ComputerName "google.com" -Port 443