ipconfig /all - Shows a detailed list of the current IP configuration. This includes:

• DNS suffix

• Description of network adapter

• MAC address

• If DHCP is enabled or not

• If autoconfiguration is enabled or not

• Link-local IPv6 address

• IPv4 address

• Subnet mask

• DHCP lease obtained and expiration times

• Default gateway

• DHCP server address

• DHCPv6 identity association identifier (IAID)

• DHCPv6 client unique identifier (DUID)

• DNS server addresses

• If NetBIOS is enabled or not

ipconfig /release - Releases or clears the current IP configuration. Use this command with the /renew switch to troubleshoot DHCP configuration problems.

• You can also use it if the device has obtained an APIPA address.

ipconfig /renew - Receives a new IP configuration from the DHCP server. Use it with the /release command to troubleshoot DHCP configuration problems.
ipconfig /flushdns - Removes all entries from the DNS Resolver Cache. Use it to troubleshoot issues with DNS.

ipconfig /registerdns - Refreshes all DHCP leases and reregisters DNS names. Use it to troubleshoot issues with DNS.
ipconfig /displaydns - Displays the contents of the DNS Resolver Cache. Use it to troubleshoot issues with DNS
arp - arp -a shows the IP address-to-MAC address mapping table (the address cache).
arp table - arp table allows a system to build frames targeting remote MAC addresses.

netstat: netstat shows the active connections. You can use the following netstat commands:

netstat -a shows detailed information for active connections.

netstat -r (route print) shows the routing table of the local host.

netstat -s shows TCP/IP statistics.

ping: Contacts the DNS server to see if it responds. Be aware that the firewall protecting the DNS server may be configured to drop ICMP (ping) packets to prevent denial of service (DoS) attacks.

If the server doesn't respond to the ping, it is not necessarily down. ping 8.8.4.4
tracert (for windows) or traceroute (for Linux)    Tests the route between your workstation and the DNS server. tracert 8.8.4.4 It will show every hop along the way to that destination. 

nslookup [host]    Queries the IP address of a host.  example:  nslookup www.mit.edu
nslookup Starts nslookup in interactive mode. The default interactive mode query is for A records, but you can use the set type= command to change the query type. nslookup set type=ns