MAC Trace

Overview

MAC Trace function shows L2 path trace based on MAC address, which is similar to the IP layer Traceroute. It is used to detect the Ethernet link connection fault, providing an effective method for Ethernet fault detection and location.

The device determines the path by using the MAC address tables of the switches in the path.

The TTL (time to live) value is 64, which specifies the lifetime of the packet and sets the maximum number of hops that the packet will go through.

NOTEs:

To make MAC trace function work, you need to enable MAC trace function on both ends of the link under test and the intermediate devices; only after this, the devices can reply to the received MAC trace messages.
MAC trace function supports only unicast destination MAC addresses.

Configuring MAC Trace

Step 1 Enable MAC trace function.

Enable MAC trace function on both ends of the link under test and on intermediate devices.

set tracemac disable <true | false>

By default, the MAC Trace function is disabled.

Only when the MAC Trace function is enabled, MAC Trace operation can be performed on the device; the device can reply to the received MAC Trace messages.

Step 2 Commit the configuration.

commit

Step 3 Perform MAC Trace detection.

Perform MAC Trace on any end of the link under test to locate the connectivity failures between the device and the destination device.

run tracemac destination <mac-address> vlan <vlan-id>

Example

Trace MAC destination device with MAC address 20:11:11:11:11:11:11 and belonging to VLAN 100.

admin@PICOS# run tracemac destination 22:11:11:11:11:11 vlan 100
Hop   Hostname    Ingress port   Ingress mac        Egress port Egress mac
----- ----------- -------------- ------------       ----------- ------------
1     PICOS       xe-1/1/1.1     70:72:cf:b7:65:45  te-1/1/5    70:72:cf:b7:65:45
2     PICOS       te-1/1/3       04:f8:f8:20:6c:7b  te-1/1/1    04:f8:f8:20:6c:7b