Quincy Center for Technical Education
Computer Technology Department

Tracert

This diagnostic utility determines the route taken to a destination by sending Internet Control Message Protocol (ICMP) echo packets with varying Time-To-Live (TTL) values to the destination. Each router along the path is required to decrement the TTL on a packet by at least 1 before forwarding it, so the TTL is effectively a hop count. When the TTL on a packet reaches 0, the router is supposed to send back an ICMP Time Exceeded message to the source system. Tracert determines the route by sending the first echo packet with a TTL of 1 and incrementing the TTL by 1 on each subsequent transmission until the target responds or the maximum TTL is reached. The route is determined by examining the ICMP Time Exceeded messages sent back by intermediate routers. However, some routers silently drop packets with expired TTL values and are invisible to tracert.

tracert [-d] [-h maximum_hops] [-j computer-list] [-w timeout] target_name

Parameters

-d

Specifies not to resolve addresses to computer names.

-h maximum_hops

Specifies maximum number of hops to search for target.

-j computer-list

Specifies loose source route along computer-list.

-w timeout

Waits the number of milliseconds specified by timeout for each reply.

target_name

Name of the target computer.