DOS Commands

Common DOS Commands

1. ping command -
ping xxx.xxx.xxx.xxx (ip address)
ping yahoo.com (web address)

Switches - You maybe use the switches together
ping xxx.xxx.xx.xx -t Allows a continuous ping. To stop the ping press Cntrl+C.
-l size Allows you to send a specific amount of data.

The Ping command is a network tool used to determine if you are able to send a set amount of information between your computer on the internet(or local network) to another computer without losing packets along the way. By doing this you can determine if you're online or if a website is down. It also calculates round trip time and Time to Live. This can let you know if your NIC card is working properly and if you're able to reach your router or modem. It can also be used as a network trouble shooting tool.

2. ipconfig command -
ipconfig Used to view your current IP values of your TCP/IP settings.
ipconfig /all To display all your IP information for all adapters.

ipconfig /release To release your current IP information.
ipconfig /renew Used to renew your IP information.

ipconfig /displaydns This shows your current DNS Resolver Logs.
ipconfig /flushdns This clears your current DNS Resolver Logs.

You would run an ipconfig if you need to find your IP address, default gateway or subnet mask. These numbers can be very helpful when trouble shooting your network connection. if you have changed your settings but they are not taking place you may try a release and renew. if you're having problems resolving to a website you may try clearing your DNS Resolver Logs.

3. tracert -
tracert yahoo.com

With Trace route you can check the path your packets take across the internet from you to your destination. Along the way you can determine the time from hop to hop. You can identify server problems and latency with this tool.

4. nslookup -
nslookup yahoo.com
nslookup xxx.xxx.xxx.xxx

nslookup is used to resolve and IP to hostname or vice versa. Hostname to IP. It can be a way to find out if your DNS is properly working or if the site is having problems. You can obtain an IP from a site and try to visit the IP directly, bypassing the Domain Name Servers that would usually resolve the Domain name to IP name.

5. netstat -
netstat

netstat can be used to view your active TCP/IP connections. You can determine what ports are being used, what programs are using your ports and what kind of TCP and UDP connections are present.

Switches
netstat -a Displays all active TCP connections. And TCP / UDP ports.
netstat -e Displays ethernet statistics.
netstat -b Displays all active programs that are listening.

6. netsh -
netsh winsock reset winsock reset
netsh int ip reset resetlog.txt TCP/IP reset

netsh is used to reset or rebuild the Windows TCP/IP IP Stack. This can be done if you have a problem with DNS. Say you are able to browse to a sites IP address but not to it's Domain Name. You can find the sites IP by using nslookup mentioned above.

7. arp -
arp -a

This command can be used to find out the MAC address of the device you are connecting to. With this information, you can find out what type of router you are connected to by using this website.

To get to the DOS Command Prompt
To get to the DOS Command prompt you simply go to your Windows Start menu, Then go to Run. When the little box pops up you type in cmd. Once the Black Command Prompt pops up you can type any of these commands in and have some fun! Another way to get the Run box is to hit your Windows Key + R at the same time.