Network troubleshooting commands

These commands can run on PowerShell and will help troubleshoot network connectivity problems.

PING - C:\>PING [device name or IP] : This command will send a signal to target device and will return a response.

Traceroute - C:\>Tracert [device name or IP] : This command will list all of the hops the signal will take from the source to the targeted device.

Test-NetConnect cmdlet - C:\tnc [hostname or IP] -port [port number]:This command will test the designated TCP port to verify if it is open or closed.  TCPTestSuceeded : Positive means the port is open.

NetStat - C:\NetStat - This command identifies all of the active network connections and network ports from your machine.

Ipconfig - C:\Ipconfig /all - This command will display all of the network values for each of the active network adapters on your machine.

Clear out DNS cache - C:\Ipconfig /flushdns - This command will clear out local DNS cache.

Release your IP address issued by DHCP - C:\Ipconfig /release - This command will release the IP address issued to your workstation by the DHCP server.  The /renew switch will reach back out to the DHCP server to obtain an IP address.

Display your local DNS cache - C:\Ipconfig /displaydns - This command will display all of the cache DNS records your workstation holds.

Display your routing records - C:\route print - This command will display the routing rules on your local workstation.

NSLookup - This command will help query a DNS server.  By default when activating NSLookup, it will query the DNS server offered by your DHCP.

NSlookup Server [DNS hostname or IP address] - This command will query this specific DNS server.

NSlookup Set type=[Record type] - This command will pull up the specific zone record of the domain name. A is the IP address, MX is the Mail Server, TXT is the Text zone record, SOA is the DNS in charge of hosting that zone record.