MS-DOS TOP 10 COMMANDS

Here are my list of the top 10 MS-DOS commands. I will give a short description of each and show you how to use them. They are listed below, click on there links to see the information. The most important parameter that apply to all of the following command is: /? This parameter display the help menu for its respective command, showing all the parameters and how to use them.

To use any or more of these commands under Microsoft Windows 2000, XP and 2003; click on Start, Run..., and type in cmd or command. See figure 1.1 to see a picture of the Run window, move your mouse over the image to see the MS-DOS window. A black MS-DOS window will appear,similar to the one in figure 1.1 when the mouse is over it, and from there you can start exploring these or other commands. The format for writing command is the following: [command] [/parameter]. When used properly, MS-DOS is an excellent tool to explore, diagnosticate and fix your computer.
fig 1.1

1- HELP
2- DIR
3- CD
4- CHKDSK
5- CLS
6- IPCONFIG
7- PING
8- NSLOOKUP
9- NETSTAT
10- TRACERT

Help - This is one of the most important commands of all. Whenever in doubt, use help! The help command list all the available MS-DOS, but does not list the MS-DOS based utilities can are considered commands, like the ones list from number 7 down. With this command, you can learn all you want about the uses of all the MS-DOS commands, listed alphabetically. To get more information on any of the help listed commands, type: help [command].
Dir - This command can speed up your search for a folder or a file in the MS-DOS window. It display all the files and folders in the directory that you are currently working in. It also display at the bottom the total amount of space the files are taking and how much free space you have on that specific drive. Furthermore, is give you the drive letter, name and serial number. Figure 1.2 shows you all of the following information, after performing the dir command.
fig 1.2
Cd - This command stands for "change directory", and does pretty much what it's name says. Figure 1.3 show a few example of how the cd command works.
fig 1.3
Chkdsk - This is a very useful command to help you detect and fix error on your hard drive. The check disk command scans your drive for problems with files, indexes and also security descriptors. After it finishes, if displays a report letting you know if any errors have been detected. It also provide a description of the repartition of files in different categories along with the size of each category. Figure 1.4 show the outcome of a scan to detect errors on the main hard drive.
fig 1.4
Cls - This is a very basic command but that can come in handy, all it does is clean the content in your MS-DOS screen, returning it to its original appearance when you opened MS-DOS.
IPconfig - This command is very useful when you have problem either working with networks or connecting to the Internet. Using this command will let you view either basic information about you IP address, subnet mask and default gate or the preceding with all the information you may need to know about your IP configuration or your network card's configuration.
The most used command parameters for ipconfig are the following:
/all Which displays the full configuration information for your network card's connection, including it's MAC address, host name, DNS suffix and much more.
/release Which releases (lets go off) your current IP that was assigned to you either by a DHCP server (router), or by your ISP.
/renew Which renews (gets a new) IP from either a DHCP server (router) or your ISP.
/flushdns Which empty's your DNS Resolver cache stored on your computer (web address and it's corresponding IP address).
Other parameters exist, but are not used as much, see the help to discover what they are and how to use them.
Ping - This command is very helpful to see if your Internet or network connection is slow and even gives you clues that your connection might not work at all. When you use the command, it send out packets of data to a specific address or server and calculates how long it takes for those packets to be returned. This time is calculated in milliseconds (ms). Figure 1.5 shows a ping on www.google.com, were we can see statistics about the time it took to send and receive packets to Google's site.
fig 1.5
You can change the number of pings, the size of the packets being sent, the time the packets have to respond before it times out and much more. There is also a interesting parameter that let's you ping a IP address and it will return it's hostname address, if there is one.
Nslookup - This command is very useful for looking up either IP address or hostnames to resolve to one another. Figure 1.6 shows Google's host name resolved to all of its corresponding IP address. Remember there can be more then one IP per hostname. To use this command, you must first enter it, type: nslookup and press Enter. Then you are able to do your IP or hostname searches. When your finished, just type: exit to leave nslookup and return to the MS-DOS window.
fig 1.6
Netstat - This command its mostly used to show many details about your network connection. It shows multiple TCP/IP network connection statistics, protocols, information about port in use and much more. This command is very useful to determine which ports are open and if connected, to who. To maintain a close watch on your network, you should at least look at this command, a lot can be learned about your current network configuration and on your computers vulnerability. Look at figure 1.7 to see just a little what netstat can do, by identifying open ports, and helping you secure your system. You can visit Shields Up!! to look up and identify what each port is normally used for.
fig 1.7
Tracert - This command it helpful to identify how many hops you need to perform before reaching your specific destination. This command is helpful to either show where different servers are slow or it there is a bottleneck between you and your destination. Figure 1.8 shows the different hops need to contact Google's site from my location.
fig 1.8
There are a few parameters that go along with this command such as to not display the hostnames, or change the amount of time under the request times out.