Basic DOS Commands

[Obtruse_Man4]

One of the most affective ways to diagnose a network problem is by the use of DOS commands. The following is a step by step guide on how to execute these commands and an explanation of what they do.

1. Click "Start"
2. Click "Run"
3. Type "command"
4. Click "ok"
5. Type "c:"
6. Press "Enter"
7. Type <commands*>
8. Press "Enter"

Several lines of text will appear on your screen

9. Right click anywhere in the command prompt window
10. Click "Mark"
11. Move your mouse to the upper left corner of the command prompt window, left-click, drag your mouse down to the bottom right corner of the window, and release your left mouse button.
12. Press "Enter"

commands*
ipconfig - displays current TCP/IP configuration

Z:\>c:

C:\>ipconfig

Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : smoothwall
IP Address. . . . . . . . . . . . : 10.10.10.6
Subnet Mask . . . . . . . . . . . : 255.0.0.0
Default Gateway . . . . . . . . . : 10.10.10.1

ipconfig /all - displays full TCP/IP configuration for all adaptors

C:\>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : evan
Primary Dns Suffix . . . . . . . : dns.windowsserver.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : dns.windowsserver.local
smoothwall
windowsserver.local

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : smoothwall
Description . . . . . . . . . . . : NVIDIA nForce Networking Controller
Physical Address. . . . . . . . . : 00-50-8D-F9-43-2D
Dhcp Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 10.10.10.6
Subnet Mask . . . . . . . . . . . : 255.0.0.0
Default Gateway . . . . . . . . . : 10.10.10.1
DHCP Server . . . . . . . . . . . : 10.10.10.1
DNS Servers . . . . . . . . . . . : 10.10.10.2
10.10.10.1
Lease Obtained. . . . . . . . . . : Friday, January 27, 2006 9:06:46 PM
Lease Expires . . . . . . . . . . : Friday, January 27, 2006 10:06:46 PM

ipconfig /flushdns - resets the clients cache

C:\>ipconfig /flushdns

Windows IP Configuration

Successfully flushed the DNS Resolver Cache.

ipconfig /release - releases current DHCP configuration

C:\>ipconfig /release

Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 0.0.0.0
Subnet Mask . . . . . . . . . . . : 0.0.0.0
Default Gateway . . . . . . . . . :

ipconfig /renew - renews DHCP configuration for all adaptors

C:\>ipconfig /renew

Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . : smoothwall
IP Address. . . . . . . . . . . . : 10.10.10.6
Subnet Mask . . . . . . . . . . . : 255.0.0.0
Default Gateway . . . . . . . . . : 10.10.10.1

tracert IP - displays the series of IP routers that are used in delivering packets from your computer to the destination and how long it took on each hop

C:\>tracert www.yahoo.com

Tracing route to www.yahoo.akadns.net [216.109.118.69]
over a maximum of 30 hops:

1 <1 ms <1 ms <1 ms 10.10.10.1
2 6 ms 6 ms 6 ms 10.69.88.1
3 7 ms 6 ms 5 ms ge-6-1-ur01.chambersburg.pa.panjde.comcast.net [68.86.217.245]
4 6 ms 7 ms 6 ms te-1-1-ur01.carlisle.pa.panjde.comcast.net [68.86.209.33]
5 6 ms 8 ms 7 ms te-1-1-ur01.epennsboro.pa.panjde.comcast.net [68.86.209.29]
6 8 ms 8 ms 7 ms te-1-1-ur01.bluemountain.pa.panjde.comcast.net [68.86.209.25]
7 8 ms 9 ms 8 ms te-2-1-ar01.lowerpaxton.pa.panjde.comcast.net [68.86.209.21]
8 10 ms 10 ms 9 ms po90-ar01.coatesville.pa.panjde.comcast.net [68.86.208.41]
9 12 ms 11 ms 11 ms po90-ar01.wallingford.pa.panjde.comcast.net [68.86.208.37]
10 12 ms 11 ms 11 ms po90-ar01.401nbroadst.pa.panjde.comcast.net [68.86.208.29]
11 14 ms 13 ms 13 ms 12.118.114.49
12 21 ms 23 ms 23 ms tbr2-p012301.phlpa.ip.att.net [12.123.137.66]
13 21 ms 22 ms 21 ms tbr1-cl9.wswdc.ip.att.net [12.122.2.85]
14 20 ms 19 ms 20 ms gar1-p300.ascva.ip.att.net [12.123.8.49]
15 * * * Request timed out.
16 19 ms 22 ms 18 ms ae1.p420.msr2.dcn.yahoo.com [216.115.96.185]
17 19 ms 20 ms 19 ms ge9-3.bas2-m.dcn.yahoo.com [216.109.120.155]
18 21 ms 20 ms 21 ms p6.www.dcn.yahoo.com [216.109.118.69]

Trace complete.