Sunday, March 25, 2012

Trouble Shooting Internet Connection Problem

The Possible solutions are given below:

Making Sure You Have Correct IP Information
For this following test may be done:
a) IP Address & Subnet Mask
b) Default Gateway
c) DNS Servers

a) IP Address testing
=> ifconfig -a
If not getting assigned ip address the reasons may be: Defective cable, network card or port on the router.

b) Default Gateway
First find out the Gateway/Router IP as following
=> netstat -nr
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
192.168.1.0     0.0.0.0         255.255.255.0   U         0 0          0 eth1
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth1
0.0.0.0         192.168.1.1     0.0.0.0         UG        0 0          0 eth1
Now ping to Gateway/Router
=> ping 192.168.1.1

c) DNS Servers
Check DNS Connection:
=> ping dns ip
If no reply from DNS server the possible reasons may be:
1. The TCP/IP suit on your computer might be corrupted
2. There is some connection issues on your network
3. There is no internet connection from your service provider.
To check whether TCP/IP suit is corrupted or not check it we need to ping the loop back address on computer.
To do ping to loopback
=>ping localhost
=>ping 127.0.0.1
If there is reply from the loop back address it shows the TCP/IP suit is working on your computer.
Check whether local network connection has any issues or not.
cont………….