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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 7 Checking Port Status and Connectivity Configuring ICMP

Running Layer 2 Traceroute

To display the physical path that a packet takes from a source device to a destination device, enter either
one of these commands:
or
These examples show how to use the traceroute mac and traceroute mac ip commands to display the
physical path a packet takes through the network to reach its destination:
Switch# traceroute mac 0000.0201.0601 0000.0201.0201
Source 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)
con6 (2.2.6.6) :Fa0/1 => Fa0/3
con5 (2.2.5.5 ) : Fa0/3 => Gi0/1
con1 (2.2.1.1 ) : Gi0/1 => Gi0/2
con2 (2.2.2.2 ) : Gi0/2 => Fa0/1
Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)
Layer 2 trace completed
Switch#
Switch# traceroute mac ip 2.2.66.66 2.2.22.22 detail
Translating IP to mac .....
2.2.66.66 => 0000.0201.0601
2.2.22.22 => 0000.0201.0201
Source 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)
con6 / WS-C2950G-24-EI / 2.2.6.6 :
Fa0/1 [auto, auto] => Fa0/3 [auto, auto]
con5 / WS-C2950G-24-EI / 2.2.5.5 :
Fa0/3 [auto, auto] => Gi0/1 [auto, auto]
con1 / WS-C3550-12G / 2.2.1.1 :
Gi0/1 [auto, auto] => Gi0/2 [auto, auto]
con2 / WS-C3550-24 / 2.2.2.2 :
Gi0/2 [auto, auto] => Fa0/1 [auto, auto]
Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)
Layer 2 trace completed.
Switch#
Configuring ICMP
Internet Control Message Protocol (ICMP) provides many services that control and manage IP
connections. ICMP messages are sent by routers or access servers to hosts or other routers when a
problem is discovered with the Internet header. For detailed information on ICMP, refer to RFC 792.
Command Purpose
Switch# traceroute mac {source-mac-address}
{destination-mac-address}Runs Layer 2 traceroute to trace the path that
packets take through the network.
Command Purpose
Switch# traceroute mac ip {source-mac-address}
{destination-mac-address}Runs IP traceroute to trace the path that
packets take through the network.