Summary; Using Layer 2 Traceroute; Understanding Layer 2 Traceroute - Cisco ME 3400G-2CS - Ethernet Access Switch Software Configuration Manual

Chapter 36 Troubleshooting

Summary

Keep these guidelines in mind while pinging:
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If your switch is running the metro IP access image, use one of these methods to ping a host connected
to a UNI:
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To end a ping session, simultaneously press and release the Ctrl, Shift, and 6 keys, and then press the
X key.

Using Layer 2 Traceroute

These sections contain this information:
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Understanding Layer 2 Traceroute

The Layer 2 traceroute feature allows the switch to identify the physical path that a packet takes from a
source device to a destination device. Layer 2 traceroute supports only unicast source and destination
MAC addresses. It finds the path by using the MAC address tables of the switches in the path. When the
switch detects a device in the path that does not support Layer 2 traceroute, the switch continues to send
Layer 2 trace queries and lets them time out.
Note Layer 2 traceroute is available only on NNIs.
The switch can only identify the path from the source device to the destination device. It cannot identify
the path that a packet takes from source host to the source device or from the destination device to the
destination host.
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IP routing is available only with the metro IP access image and is disabled by default.
To ping a host in a different IP subnetwork from the switch, you must have IP routing configured to
route between the subnets, and a static route to the destination might also be appropriate. If you need
to enable or configure IP routing, see
All software versions can use a Layer 3 service policy to permit pings to and from a host connected
to a UNI. For more information about policy maps, see the
page 30-4.
Use a Layer 3 service policy to permit pings to and from a host connected to a UNI.
Enable global IP routing and configure a port as a routed port by using the no switchport interface
configuration command.
Enable global IP routing, create an SVI, and assign an IP address to it. For more information about
SVIs, see the "Switch Virtual Interfaces" section on page
Understanding Layer 2 Traceroute, page 36-13
Layer 2 Traceroute Usage Guidelines, page 36-14
Displaying the Physical Path, page 36-15
Chapter 32, "Configuring IP Unicast Routing."
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
Using Layer 2 Traceroute
"Input and Output Policies" section on
9-5.
36-13