3 Simple Network Troubleshooting Commands

I know that most of you are always panicking whenever you can’t connect to another PC (if your in a network) or the internet. And before you get all jumpy and start bothering your IT well there are 3 simple commands that you can use to test your network.

Ping

also short for Packet InterNet Gropher or Packet Inter-Net Gropher is a computer network tool used to test whether a particular host is reachable across an IP network; it is also used to self test the network interface card of the computer, or as a speed test. It works by sending ICMP “echo request” packets to the target host and listening for ICMP “echo response” replies. Ping estimates the round-trip time, generally in milliseconds, and records any packet loss, and prints a statistical summary when finished.

source: http://www.wikipedia.org

Ping is always the first tool to use whenever you are dealing with TCP/IP problems. The Ping command is particularly useful when troubleshooting a network connectivity problems in a routed environment because it can be used to diagnose exactly where the routing breaks down. If your having trouble connecting to a particular server in a remote network, you can use ping to determine if the problem is in your network, the remote network, or any network in between by pinging hosts and routers along the entire route. (of course this includes a website)

Here is how to run the PING command (for windows users):

• Click the Start Menu
• Click Run
• Then a Run window will appear for the (image click here), then type “command” or “cmd” to open a command prompt

• Then type the following syntax : ping (IP address)
• Then a result will appear

• You can also use a web URL to replace the IP Address like for example:

Now if there is a reply or a 0% Loss, it means that your target host, LAN Card, or web URL is working perfectly fine. Now if it doesn’t here is a lis of possible errors that may occur in the event of a connectivity problem:

• Unknown Host – This usually indicates that the name cannot be resolved.
• Destination Host Unreachable – This indicates that a route to the destination is not available.
• Request Timed Out – This meands that there was no response to the Ping in the default time period (which is 1 second). This indicates that there might be a router down, the destination host is down, or there is no return route back to the sending host.

For more information about the syntax of the Ping command just type: “ping /?” in the command prompt

Tracert

is a computer network tool used to determine the route taken by packets across an IP network. An IPv6 variant, traceroute6, is also widely available.

Traceroute is often used for network troubleshooting. By showing a list of routers traversed, it allows the user to identify the path taken to reach a particular destination on the network. This can help identify routing problems or firewalls that may be blocking access to a site. Traceroute is also used by penetration testers to gather information about network infrastructure and IP ranges around a given host. It can also be used when downloading data, and if there are multiple mirrors available for the same piece of data, one can trace each mirror to get a good idea of which mirror would be the fastest to use.

source: http://www.wikipedia.org

Tracert utility is used to test a path between a host and a destination computer. The difference between Tracert and Ping is that Tracert will list each IP router that is used to deliver packets from the host to the destination as well as the time that each packet remained at each hop.

To run the Tracert command (for windows users):

• Click the Start Menu
• Click Run
• Then a Run window will appear for the (image click here), then type “command” or “cmd” to open a command prompt
• Type the following syntax for tracert: tracert (IP address or Web URL)

For more information about the syntax of the Tracert command just type: “tracert /?” in the command prompt

Pathping

is a network utility supplied in Windows NT, Windows 2000, Windows 2003, Windows XP and Windows Vista. It combines the functionality of Ping with that of Traceroute (in Windows: tracert), by providing details of the path between two hosts and Ping-like statistics for each node in the path based on samples taken over a time period, depending on how many nodes are between the start and end host. The advantages of pathping over ping and traceroute are that each node is pinged as the result of a single command, and that the behavior of nodes is studied over an extended time period, rather than the Ping’s default sample of four messages or Traceroute’s default single route trace. The disadvantage is that, using the default settings, it often takes more than five minutes to produce a result.

source: http://www.wikipedia.org

The Pathping tool is a route-tracing tool that combines the features of Ping and Tracert. This tool also provides statistics on the degree of packet loss at each computer. This is convenient for determining which router or link is causing network problems.

To run the Pathping command (for windows users):

• Click the Start Menu
• Click Run
• Then a Run window will appear for the (image click here), then type “command” or “cmd” to open a command prompt
• Type the following syntax for pathping: pathping (IP address or Web URL)

For more information about the syntax of the Pathping command just type: “pathping /?” in the command prompt

Well there you go! But if all else fails, you still can call your IT.