Networking Commands & Trouble shooting

Network commands and Trouble shooting steps..

Network commands.

Winipcfg or Ipconfig /all

Ipconfig is a DOS utility, which can be used from MS-DOS to display the network settings currently assigned and given by a network. This command can be utilized to verify a network connection as well as to verify your network settings.
netstat

Displays active TCP connections, ports on which the computer is listening, Ethernet statistics, the IP routing table, IPv4 statistics (for the IP, ICMP, TCP, and UDP rotocols), and IPv6 statistics (for the IPv6, ICMPv6, TCP over IPv6, and UDP over IPv6 protocols). Used without parameters, netstat displays active TCP connections.
tracert

The tracert command is used to visually see a network packet being sent and received             and the amount of hops required for that packet to get to its destination. Users with Microsoft Windows 2000 and Windows XP who need additional information network latency and network loss should also consider using the pathping command.
ping

Helps in determining TCP/IP Networks IP address as well as determine issues with the network and assists in resolving them.
pathping

Provides information about network latency and network loss at intermediate hops between a source and destination. Pathping sends multiple Echo Request messages to each router between a source and destination over a period of time and then computes results based on the packets returned from each router

.
telnet
Telnet is software that allows users to remotely access another computer such as a server, network device, or other computer. With telnet users can connect to a device or computer, manage a network device, setup a device, transfer files, etc.
ftp
FTP is short for File Transfer Protocol, this page contains additional information about the FTP command and help using that command in Unix and MS-DOS (Windows).
Net view

To find how many computers are online.

net send

For messaging between computers.  For e.g net send Pc1 hello I am fine.

route
The function and syntax of the Windows ROUTE command is similar to the UNIX or Linux route command. Use the command to manually configure the routes in the routing table.

arp
Displays, adds, and removes arp information from network devices.
nslookup
Displays information that you can use to diagnose Domain Name System (DNS) infrastructure. Before using this tool, you should be familiar with how DNS works. The Nslookup command-line tool is available only if you have installed the TCP/IP protocol.

General Trouble shooting in a LAN

Command	Target	What Ping Failure Indicates
ping 127.0.0.1	Loopback address	Corrupted TCP/IP installation
ping localhost	Loopback name	Corrupted TCP/IP installation
ping 192.168.1.1*	This computer’s IP address	Corrupted TCP/IP installation
ping PC1	This computer’s name	Corrupted TCP/IP installation
ping 192.168.1.2	Another computer’s IP address	Bad hardware or NIC driver
ping PC2	Another computer’s name	NetBIOS name resolution failure

*PC should be connected to a hub/switch/modem

Trouble shooting in Internet.

You can also use ping to find a problem with Internet access.  Run these commands in the order shown, and don’t go on to the next command until all of the previous commands work properly.  Use the Default Gateway and DNS Server addresses that you got from the winipcfg or ipconfig /all command. 

Command	Target	What Ping Failure Indicates
ping w.x.y.z	Default Gateway	Default Gateway down
ping w.x.y.z	DNS Server	DNS Server down
ping w.x.y.z	Web site IP address	Internet service provider or web site down
ping www.something.com	Web site name	DNS Server down or web site down

If all the things are okay, then browse with the IP in Internet explorer or mycomputer window.

Problem 1.

Network connection has IP address 169.254.x.x

DHCP is down. This is automatic private IP allocation. Verify whether DHCP service is on.

Give the command ipconfig /renew.

Problem 2.

Network connection configured to obtain an IP address automatically has IP address 0.0.0.0

Right click My Computer, and click Manage. Double click Services and Applications. Double click Services. Double click DHCP Client. If the Service status is stopped, click Start. Set the Startup type to Automatic.

      Problem 3.           

      Computers can ping each other by IP address, but not by name.     

                        Enable netBios over TCP/IP. (TCP/IP-advanced-WINS)

      Problem 4.

      Error Message: Network Cable Unplugged

Don’t take this message literally – there are many causes besides not having a cable physically plugged into the network card. The message really means that the network card doesn’t detect a live link to another device on the other end of the cable.

Solutions:

Check the cabling – a bad cable will prevent link detection. Substitute a cable that’s known to be good. Check the link lights on the device on the other end of the cable, whether it’s a hub, switch, router, or a NIC in another computer. It should show a live link to the NIC. If it doesn’t, try a different port.

    Problem 5.

    Error Message: The list of servers for this workgroup is not currently available.

Right click My Computer, and click Manage.

Double click Services and Applications.

Double click Services.

Double click Computer Browser. If the Service status is Stopped, click Start.

Set the Startup type to Automatic.

   Problem 5.

   Computer A Can Ping Computer B, but not Vice Versa

This is almost always caused by an improperly configured firewall on Computer A.

    Problem 6.

    XP's Network Setup Wizard Says That No Network Card Is Installed

XP's Network Setup Wizard sometimes fails to recognize an installed and working network card. This is because the NIC's driver program doesn't respond correctly to all of the queries that the Wizard makes when it's looking for a NIC. Configure the card’s TCP/IP properties manually.

    Problem 7.

   Error Message - PING: transmit failed, error code 65

This error message occurs when you try to ping any IP address. A firewall program has been incompletely removed.

     Problem 8.

    A shared disk or folder doesn’t appear in My Network Places

The disk or folder is shared correctly on another computer, but it doesn’t appear.

Solution 1: Click Add a network place and follow the prompts to add it. Browse to it through Entire Network, or specify the path name using the form \\computer\share.

Solution 2: Click View workgroup computers, then click the computer that has the shared disk or folder.

      Note : In BSNL Broadband the following errors indicate,

Error-769         -           Enable/Disable             LAN
Error- 797        -           LAN-Driver Error                   
Error-718         -           Overloading BRAS during Peak hour
Error-678         -           Common problem in connectivity.
Error-691         -           Password