While trouble shooting, using below basic command checks leads to resolving issues 60% faster.
Ping Test: This is to check if end device is reachable or not
Command: ping "IP Address" -t ( -t is for continuous probing)
For more info and additional commands, check below link and use as per need.
If not end device is not reachable:
Route Test: This is to be used of end device is not reachable, route command will check what network route is taken.
Command: tracert "IP Address" -d ( -d is used to avoid hostname check and get output results faster)
For more info and additional commands, check below link and use as per need.
If end device is reachable, but application or cannot connect to end device: ( Example, while placing a phone or video call. End device is reachable, but call is not connected)
Telnet: This command is to check if TCP port is open in network or not
Command: telnet "IP Address" "port no" ( by default telnet " IP Address" connects to port 23 )
For more info and additional commands, check below link and use as per need.
Other Commands:
Netstat: To check for TCP connections in windows system
For more info and additional commands, check below link and use as per need.
Nslookup: To check host name resolution
nslookup "host name/domain name"
For more info and additional commands, check below link and use as per need.