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Tracert is generally used to determine the route or path taken to a destination by sending ICMP packets with varying Time to Live (TTL) values. Each router the packet meets on the way decreases the value of the TTL by at least one; invariably, the TTL is a hop count. The path is determined by checking the ICMP Time Exceeded messages returned by intermediate routers. Some routers do not return Time Exceeded messages for expired TTL values and are not captured by Tracert. In such cases, asterisks are displayed for that hop.

To display the different parameters that can be used with Tracert, open a command prompt and type tracert (without parameters) to display help or type tracert /?. The parameters associated with Tracert are as follows:

. -4—Specifies that tracert.exe can use only IPv4 for the trace.

. -6—Specifies that tracert.exe can use only IPv6 for the trace.

. -d—Prevents resolution of IP addresses of routers to their hostname. This is particularly useful for speeding up results of Tracert.

. -h maximumHops—Specifies the maximum number of hops to take before reaching the destination. The default is 30 hops.

. -j HostList—Specifies that packets use the loose source route option. Loose source routing allows successive intermediate destinations to be separated by one or multiple routers. The maximum number of addresses in the host list is nine. This parameter is useful only when tracing IPv4 addresses.

. -R—Sends packets to a destination in IPv6, using the destination as an intermediate destination and testing reverse route.

. -S—Specifies the source address to use. This parameter is useful only when tracing IPv6 addresses.

. -w timeout—Specifies the time in milliseconds to wait for each reply.

Tracert is a good utility to determine the number of hops and the latency of communications between two points. Even if an organization has an extremely high-speed connection to the Internet, if the Internet is congested or if the route a packet must follow requires forwarding the information between several routers along the way, the performance and, ultimately, the latency (or delay in response between servers) will cause noticeable communications delays.

Source of Information : Sams - Windows Server 2008 R2 Unleashed (2010)