Traceroute when an error is detected

Each time an error is detected by a remote Dotcom-Monitor agent location, it automatically executes a traceroute from that remote monitoring agent location to the target of the monitoring.

A traceroute can help determine if the error is an issue related to the network itself – such as DNS resolution issue, packet loss, or a network latency  – or if the error is an actual server problem.

There are two types of traceroute procedures: Network traceroute and DNS traceroute.

Network traceroute

A Network traceroute will help identify the network hop where the problem is occurring. This helps identify whether or not the issue is actually within the user’s organization or within the user’s direct control. If the Network traceroute shows no packet loss and average latency, then the traceroute is helping to pinpoint that the issue is not network-related and likely an issue with the server itself.

Dotcom-Monitor attaches traceroute to each error, except DNS errors

Traceroute is being captured in 4 iterations with 30 hop limit for each. Timeoutе for each request is 4 seconds.

Summary table contains Best/Average/Worst latency values returned for each router along the path, calculated based on all 4 iterations.

Example of final traceroute columns:

traceroute_png

In case path changes during iterations execution, the first path will be displayed.

DNS traceroute

As domain name service (DNS) traceroute is a great tool for identifying issues with DNS. It shows you how DNS requests go through all the steps of a DNS hierarchy, from ROOT servers to your local DNS. If the DNS traceroute to one of the DNS doesn’t respond, or responds incorrectly, you can find it in the results of the DNS traceroute. Next Video shows how to troubleshoot DNS Errors via DNS Traceroute :