1tracert role
It is used to explore the source address to a destination address which route through. And each reach a point, a signal is returned to the source address. To access, for example, A D, which after then B, then C. after When B passes, a signal is returned to the A, C when passing, a signal A returns again, the last reached D, to the return signal, the process ends. Among these it should be noted that two points, after the node needs to have an IP address to return the signal, like a normal switch or hub, no IP address, there can be no return signal. Second, networks are bi-directional, as in the example above, if we find tracert D, but to C has no signal is returned, does not mean that the signal can not get D, there may be a signal to, but half-way node can not return signal only.
2. Usage
Format:
tracert [-d] [-h maximum_hops] [-j host-list] [-w timeout] [-R] [-S srcaddr] [-4] [-6] target_name
①、-d
They said they did not resolve addresses to host names.
②、-h maximum_hops
It represents the maximum number of hops search target.
③、-j host-list
It represents a loose source route list together with a host (only applies to IPv4).
④、-w timeout
Each represents waiting for a response over time (in milliseconds).
⑤、-R
Round trip path represents the track (only for IPv6).
⑥、-S srcaddr
It indicates that the source address to use (only for IPv6).
⑦, -4 and -6
It represents the mandatory use of IPv4 or IPv6.
⑧、target_name
It indicates the name or IP address of the destination host.
3 operating results
Here we tracert Baidu
By sending a different IP survival time (the target TTL ) "Internet Control Message Protocol (values ICMP )" echo packets, Tracert diagnostic procedures to determine the route taken to a destination. On each path requires a router in the packet before forwarding the packet on at least the TTL is decremented by 1. The packet TTL becomes 0, the router should be " the ICMP Time Exceeded" message back to the source system. Tracert first transmission TTL response packet 1, and each subsequent transmission process TTL incremented by 1, until the target response or the TTL reaches a maximum, to determine the route. By examining the intermediate routers send back " the ICMP Time Exceeded" message to determine the routing.
tracert command is used to determine the path of IP packets to access the target taken, showing a series of network access speed from the local node to a destination site where the web server, can display up to 30 network nodes.
Leftmost, 1 to 10 represent different routing node I to Baidu's.
Three intermediate units of ms, whereas we are showing is connected to the speed of each routing node, and returns the average of multiple link speed feedback;
Behind the IP, each routing node is the corresponding IP.
If the return message is timed out, it means that the current broadband routing nodes and we are using, is not China Unicom, such as specially made on the route filtering limit, or is the problem of routing, etc., that said it could not connect.
If the test of time, a large number are * and return times out, it shows that IP, in each routing node has a problem.
Generally less than 10 nodes can be completed website tracking, access speed is good; to complete website tracking within 10-15 nodes, the access speed is relatively poor, and if more than 30 nodes were not completed website tracking, then It can be considered the destination site is not accessible.