This article contains information about Netsh commands you can use to troubleshoot network issues.
Netsh commands are useful when you have any type of network issue. The following commands have fixed Internet browser to domain issues.
Run the Commands in Command Line as Administrator (The Command Prompt: What It Is and How to Use It on a Dell System) for the best results. Reboot after the last command, instead of rebooting in-between each command.
netsh i i r r
netsh i i de ar
netsh winsock reset
netsh advfirewall reset
Reboot the system.
This should save you a chunk of time by bypassing some troubleshooting steps. If you want to dig deeper on the exact issue, continue to read below on how this works:
In order, this is what you are resetting. TCP/IP, ARP, Winsock, Firewall, and last DNS. This method works due to the order or the resets. The order is based on how packets get packed up and sent out into the world. The first three involve the packet encapsulation process and adds info to the packet headers for routing purposes. The firewall will allow the packets to go out to the world based on rules. Generally this reset helps if you cannot ping out but can ping the gateway. Last is DNS and will need to be reset if the firewall is letting the packets go out but the destination host is not being resolved.
To test to see where the network issue is happening try this:
- Ping the loopback. This will test that the TCP/IP stack is working and if the drivers for the NIC are operating. Once the NIC drivers are updated, and no bangs in DM run the following command in cmd. If it fails, you will reset TCP/IP.
The command is: ping 127.0.0.1
- Next ping the default gateway. This may also be the router. To find the gateway's IP, type ipconfig /all in command prompt. Then ping that number found for the default gateway. ARP deals with adding MAC address resolution address to the packet headers. Based on the Operating System Reinstall (OSRI) model this is layer 3 and MAC address and routers fall in this category. If this fails, it means that the ARP needs to be reset.
The command is: ping (IP found for their default gateway) - for example: ping 192.168.1.1
- If the above steps are successful, go ahead and try to ping out to the Internet. This will test both the firewall and the DNS portions of the protocol stack. Start by pinging google.com. If it passes without errors and the customer is unable to browse online, this is a firewall issue. It would be best to reset the firewall.
If the ping test fails using the Google address, ping Google's IP address of 18.104.22.168
If the pinged Google address fails but directly pinging the IP for the site passes, it is most likely a DNS issue on the site side. If this happens, you can ping Google's DNS directly at 22.214.171.124 to determine that a non-ISP DNS server can be reached.
Go ahead and reset DNS, reboot, and retry the above commands to verify that the DNS issue is resolved. If it fails again, we can determine that the protocols on the system are good but their ISP's DNS servers are having issues. You can manually set DNS to Google's 126.96.36.199 address.
If needed, here is a link on how to manually set the IP for DNS: https://developers.google.com/speed/public-dns/docs/using#windows
If you have further questions about this solution, contact Dell Technical Support.