Simple DOS IP Packet Checks (Instructions)

To confirm if packet loss is occurring:
  1. At  Start Menu type  "cmd".
  2. Type "ping -n 20 8.8.8.8". ...
  3. Once the command has run, a summary will be presented indicating if loss occurred.
To check IP address is working:
  1. Type ping :serveraddress”.com and press the Enter key. The word ping is followed by a space and then the name of a server or an IP address
  2. Ie: ping annastaqueria.com
To check for packet loss:
  1. Open a command prompt on a client PC, via the Start Menu search for "cmd".
  2. Type "ping -n 20 8.8.8.8".
    This will ping the address 8.8.8.8 20 times. Substitute 8.8.8.8 with whatever address must be tested to.
  3. Once the command has run, a summary will be presented indicating if loss occurred.
    218a5086-e92a-4f58-ad79-b4a3e547d419
  4. If no loss occurred, try increasing the "-n" value to something higher (such as 100) to test for a longer period of time.
Note: This only tests for packet loss impacting ICMP or all traffic. Protocol specific loss may not be reflected.

If there is packet loss:

If packet loss was seen, the next step is to identify where the packet loss begins to occur. 'tracert' can be used to check each layer 3 device along the path to the destination:

  1. Open a command prompt on a client PC,via the Start Menu search for "cmd".
  2. Type "tracert -d 8.8.8.8".
    This will perform a trace route to 8.8.8.8 and present each hop as an IP address. Substitute 8.8.8.8 with whatever address must be tested to.
  3. Wait for the trace to complete, or press CTRL+C if multiple lines ending with "Request timed out" are encountered.
A lack of response will be represented by an asterisk (*), potentially indicating packet loss, or that the device is configured to not respond. The test may need to be completed multiple times to identify where loss is occurring. If packet loss is frequently encountered after a particular hop, then the issue most likely is with that device or between it and the previous hop. This screenshot illustrates a tracert clear of packet loss. The only device to not respond (hop 11) is likely configured to do so, as there is no packet loss after it.
616dd905-168b-4026-bd10-bf06a51ebddb
In this next screenshot, packet loss is regularly encountered beginning with hop 2. This indicates there may be an issue with the ISP gateway, or the link(s) between the Client gateway and ISP gateway. It is recommended to test from multiple clients at different locations in the network to help rule out specific client issues and develop commonality between clients experiencing the problem.
896f46bf-49c0-4d6b-9d20-e277274894e0
As a more robust test, the tool MTR can be used to perform a continuous series of traces and present a % of loss at each hop in the path to more clearly identify where the loss is occurring. Output for the above scenario would appear similar to:
58f7760e-1d1e-40ad-ab89-e7ca0ad3aa77

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