This diagnostic tool determines the path taken to a destination by sending Internet Control Message Protocol (ICMP) echo Request or ICMPv6 messages to the destination with incrementally increasing time to live (TTL) field values. It requires each router along the path to decrement the TTL in an IP packet by at least 1 before forwarding it. Effectively, the TTL is a maximum link counter. When the TTL on a packet reaches 0, the router is expected to return an ICMP time exceeded message to the source computer.
This command determines the path by sending the first echo Request message with a TTL of 1 and incrementing the TTL by 1 on each subsequent transmission until the target responds or the maximum number of hops is reached. The maximum number of hops equals 30 by default and you can specify the number of hops.
The tool determines the path by examining the ICMP time exceeded messages returned by intermediate routers and the echo Reply message returned by the destination. However, some routers do not return time Exceeded messages for packets with expired TTL values and are invisible to the tracert command. In this case, the tool displays a row of asterisks (
*) for that hop. The tool defines the near/side interface as the interface of the router that is closest to the sending host in the path.
The availability of this command depend on whether or not you have the Internet Protocol (TCP/IP) protocol installed as a component in the properties of a network adapter in Network Connections.
To trace a path and provide network latency and packet loss for each router and link in the path, use the pathping command.
tracert [/d] [/h <maximumhops>] [/j <hostlist>] [/w <timeout>] [/R] [/S <srcaddr>] [/4][/6] <targetname>
|/d||Stops attempts to resolve the IP addresses of intermediate routers to their names. This can speed up the return of results.|
||Specifies the maximum number of hops in the path to search for the target (destination). The default is 30 hops.|
||Specifies that echo Request messages use the Loose Source Route option in the IP header with the set of intermediate destinations specified in
||Specifies the amount of time in milliseconds to wait for the receipt of ICMP time Exceeded or echo Reply message corresponding to a given echo Request message. If not received within the time-out, the tool displays an asterisk (
|/R||Specifies that the IPv6 Routing extension header sends an echo request message to the local host, using the destination as an intermediate destination and testing the reverse route.|
||Specifies the source address to use in the echo Request messages. Use this parameter only when tracing IPv6 addresses.|
|/4||Specifies that tracert.exe can use only IPv4 for this trace.|
|/6||Specifies that tracert.exe can use only IPv6 for this trace.|
||Specifies the destination, identified either by IP address or host name.|
|/?||Displays help at the command prompt.|
To trace the path to the host named corp7.microsoft.com, type:
To trace the path to the host named corp7.microsoft.com and prevent the resolution of each IP address to its name, type:
tracert /d corp7.microsoft.com
To trace the path to the host named corp7.microsoft.com and use the loose source route 10.12.0.1/10.29.3.1/10.1.44.1, type:
tracert /j 10.12.0.1 10.29.3.1 10.1.44.1 corp7.microsoft.com