3com 3031 Instruccion De Instalación
38
C
HAPTER
5: S
YSTEM
M
ANAGEMENT
M
AINTENANCE
Reply from 202.38.160.244 : bytes=56 sequence=5 ttl=255 time = 2ms
--202.38.160.244 ping statistics--
5 packets transmitted
5 packets received
0% packet loss
round-trip min/avg/max = 1/2/3 ms
tracert
tracert
is used to test the gateways that a packet sent by the host will pass by in
order to reach the destination. It is mainly used to test whether a network
connection is reachable and to locate the position where faults occur on the
network.
connection is reachable and to locate the position where faults occur on the
network.
The
tracert
command is executed following this procedure: The system first
sends a packet with TTL as 1 and the first hop returns an ICMP error message
indicating that the packet cannot be transmitted due to TTL timeout. And then the
system transmits the packet again with TTL being set to 2 and the second hop
returns TTL timeout message similarly. This process continues until the packet
reaches its destination. The purpose of such a process is to record the source
addresses where these ICMP TTL timeout messages are sent so as to outline the
path along which the IP packet can reach the destination.
indicating that the packet cannot be transmitted due to TTL timeout. And then the
system transmits the packet again with TTL being set to 2 and the second hop
returns TTL timeout message similarly. This process continues until the packet
reaches its destination. The purpose of such a process is to record the source
addresses where these ICMP TTL timeout messages are sent so as to outline the
path along which the IP packet can reach the destination.
Perform the following operation in any view.
For more information about the options and parameters of the command, refer to
the section introducing the
the section introducing the
tracert
command in the Command Reference
Manual.
Following are examples of using
tracert
for network analysis.
Example 1:
<3Com>tracert 35.1.1.48
traceroute to nis.nsf.net (35.1.1.48), 30 hops max, 56 byte packet
1 helios.ee.lbl.gov (128.3.112.1) 19 ms 19 ms 0 ms
2 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 39 ms 19 ms
3 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 39 ms 40 ms 39 ms
4 ccn-nerif22.Berkeley.EDU (128.32.168.22) 39 ms 39 ms 39 ms
5 128.32.197.4 (128.32.197.4) 40 ms 59 ms 59 ms
6 131.119.2.5 (131.119.2.5) 59 ms 59 ms 59 ms
7 129.140.70.13 (129.140.70.13) 99 ms 99 ms 80 ms
8 129.140.71.6 (129.140.71.6) 139 ms 239 ms 319 ms
9 129.140.81.7 (129.140.81.7) 220 ms 199 ms 199 ms
10 nic.merit.edu (35.1.1.48) 239 ms 239 ms 239 ms
The information displayed above gives the GWs between the source host and the
destination, which is very helpful in network analysis.
destination, which is very helpful in network analysis.
Table 22 The
tracert
command
Operation
Command
Trace Route
tracert [-a X.X.X.X ] [ -f first_TTL ] [ -m max_TTL ] [
-p port ] [ -q nqueries ] [ vpn-instance
vpn-instance-name ] [ -w timeout ] host
-p port ] [ -q nqueries ] [ vpn-instance
vpn-instance-name ] [ -w timeout ] host