Troubleshooting Client Network Connection Problems

How to resolve client network connection problem:

1)  Take a quick look at the physical connection to ensure the cat 5 cable is properly connected.  On some laptops, you will see a flashing light indicating some level of connectivity.

2)  Using a command window, type in ipconfig /all.  The results should look something like this.



3)  The physical connection for the ethernet adapter is the last one called Realtek.  The other ones are for VMware server that I am also running.  Note that in this instance this workstation is not using DHCP.  The ip address being used is 192.168.1.91 and the gateway is 192.168.1.1.   This means I am using a static ip rather than one being dynamically issued by a DHCP server.  If I was using a DHCP server, the only difference you might is that DHCP is enabled with all the rest being the same.  You may want to confirm if this is the correct DHCP server.  For example if you are using a wireless connection, it is possible for you to connect to a router other than the one you are expecting.

4)  Assuming there is no issue with the DHCP server and what IP address, subnet mask, default gateway and DNS servers being issued there are a few other checks to be made.

a)  Ping 127.0.0.1  This is the localhost address and will work if TCP/IP stack is OK.  If this fails, you should re-install TCP/IP.

b)  Ping the local address.  In my example, this would be ping 192.168.1.91.  This will confirm the IP address for the client has successfully been bound to the physical card.  If this fails, either the drivers for the network card is problematic or the network card itself is failing or has failed.  I would first try to re-install the drivers.

c)  Ping default gateway.  In my example, this would be ping 192.168.1.1.  This will help confirm the connectivity to another device in your network.  If this fails, check the physical connections including the cable itself from the client to the default gateway device.

d)  If there are other intermediate devices such as a switch, you will need to investigate.  Commands such as tracert could be useful.

e)  Ping remote IP address.  If you are debugging a problem at home, the next IP address I would ping is the cable modem.  For me, I know the IP address is 192.168.100.1.  If you can get to that, I could try the ISP gateway.  In my example the IP address is 64.71.255.198.  From here, you could try other ones you know.