Ping –t command and its use
Ping –t is the most commonly used network command that is used by admins and technicians to check the network connectivity or to troubleshoot a network.
Using the ping without the –t switch will only send 4 packets and will receive 4 response packets from the end device as shown in the below image.
Using the ping command with the –t switch will continuously send packets to the end device until manually stopped using the Ctrl + C on the keyboard.
We can see in the image below that the ping –t command sends the ping packets continuously to the remote device and we used the Ctrl +C button to halt the pings.
How ping –t command can be used to troubleshoot the networks
Network slowness or intermittent issues
When there is a slowness in the network or usually when we observe intermittent issues while using the internet then we can use this command to check if the remote device is sending the ping reply regularly and how much is the delay while sending the reply.
Using only the ping command does not provide a clear view of the network as we may not see any slowness or packet loss with 4 ping requests but when we use the –t switch, it will provide us a more insightful view of the network state.
In the following image, we can see that ping replies are timed out in between which confirms the issue with either with the remote device or with the connection. Now, we can troubleshoot further to fix the actual issue with the device.
If our internet is not working properly, we can use the Ping –t command to check if there is any slowness in the ping request or request timing out.
We can ping any public site like google.com, Bing.com, etc to check the internet.
We can use this ping –t command to test our network
This command is very useful while testing the network devices and their performance, In big companies, there are fail-over mechanisms implemented that route the traffic to other links when one link fails.
We can test how our network is performing in fail-over. We can ping using the –t switch and see how much time the network is taking to come back up.
While using the redundant links between switches, the spanning tree protocol is used by the switches to block the redundant link so we can test how the spanning tree is performing in our network.
We have a following lab where we will simulate fail-over and see how much time the network is taking to come back online.
In this practice lab, we have three switches that provide a scope of redundancy in case one switch or link is down.
Switch 1 has blocked its link to prevent the loop in the network and we can see that the color of the port is amber which means it’s in standby mode and only be used if there is an issue with the current traffic path.
Now the traffic is traveling via switch 0, we will manually bring down the switch 0 to see the fail-over process in action.
We will ping PC1 from PC0 with the –t switch to see how much time the network takes to establish connectivity again.
We can see that the amber light turns green which brings the network back online and we are receiving the ping replies again.
We can see all the live action in the above animation.
Ping –t command is a great tool for network admins that helps them manage and fix network issues.
