3com 8807 Reference Guide
1038
C
HAPTER
61: S
YSTEM
M
AINTENANCE
C
OMMANDS
string: IP address of the destination host or the hostname of the remote system.
Description
Use the command to Using tracert command, you can check the reachability of
network connection and troubleshoot the network. User can test gateways passed
by the packets transmitted from the host to the destination.
network connection and troubleshoot the network. User can test gateways passed
by the packets transmitted from the host to the destination.
By default, when the parameters are not specified,
The tracert command sends a packet with TTL 1, and the first hop will send an
ICMP error message back to indicate this packet cannot be transmitted (because
of TTL timeout). Then this packet will be sent again with TTL 2, and the second
hop will indicate a TTL timeout error. Perform this operation repeatedly till
reaching the destination. These processes are operated to record the source
address of each ICMP TTL timeout so as to provide a path to the destination for an
IP packet.
ICMP error message back to indicate this packet cannot be transmitted (because
of TTL timeout). Then this packet will be sent again with TTL 2, and the second
hop will indicate a TTL timeout error. Perform this operation repeatedly till
reaching the destination. These processes are operated to record the source
address of each ICMP TTL timeout so as to provide a path to the destination for an
IP packet.
After ping command finds some error on the network, perform tracert to locate
the error.
the error.
The output of tracert command includes IP address of all the gateways to the
destination. If a certain gateway times out, output "***".
destination. If a certain gateway times out, output "***".
c
CAUTION: For the moment, you can not use the tracert command on the Switch
8800 Family routing switch to test whether the network connection is reachable
or analyze where the fault happens in the network in the MPLS domain.
8800 Family routing switch to test whether the network connection is reachable
or analyze where the fault happens in the network in the MPLS domain.
Example
# Test the gateways passed by the packets to the destination host at 18.26.0.115.
<SW8800> tracert 18.26.0.115
tracert to allspice.lcs.mit.edu (18.26.0.115), 30 hops max
1 helios.ee.lbl.gov (128.3.112.1) 0 ms 0 ms 0 ms
2 lilac-dmc.Berkeley.EDU (128.32.216.1) 19 ms 19 ms 19 ms
3 lilac-dmc.Berkeley.EDU (128.32.216.1) 39 ms 19 ms 19 ms
4 ccngw-ner-cc.Berkeley.EDU (128.32.136.23) 19 ms 39 ms 39 ms
5 ccn-nerif22.Berkeley.EDU (128.32.168.22) 20 ms 39 ms 39 ms
6 128.32.197.4 (128.32.197.4) 59 ms 119 ms 39 ms
7 131.119.2.5 (131.119.2.5) 59 ms 59 ms 39 ms
8 129.140.70.13 (129.140.70.13) 80 ms 79 ms 99 ms
9 129.140.71.6 (129.140.71.6) 139 ms 139 ms 159 ms
10 129.140.81.7 (129.140.81.7) 199 ms 180 ms 300 ms
11 129.140.72.17 (129.140.72.17) 300 ms 239 ms 239 ms
12 * * *
13 128.121.54.72 (128.121.54.72) 259 ms 499 ms 279 ms
14 * * *
15 * * *
16 * * *
17 * * *
18 ALLSPICE.LCS.MIT.EDU (18.26.0.115) 339 ms 279 ms 279 ms