trace mac-8021ag

Function

The trace mac-8021ag command enables 802.1ag MAC trace to detect connectivity faults between a MEP and an RMEP or a MIP in an MA.

Format

All views except the MA view:

trace mac-8021ag mep mep-id mep-id md md-name ma ma-name { mac mac-address | remote-mep mep-id mep-id } [ interface interface-type interface-number | -t timeout | ttl ttl ] ^*

MA view:

trace mac-8021ag mep mep-id mep-id { md md-name ma ma-name { mac mac-address | remote-mep mep-id mep-id } | mac mac-address | remote-mep mep-id mep-id } [ interface interface-type interface-number | -t timeout | ttl ttl ] ^*

Parameters

Parameter	Description	Value
mep mep-id mep-id	Specifies the ID of a MEP. The MEP must have been created using the mep mep-id command.	The value is an integer that ranges from 1 to 8191.
md md-name	Specifies the name of an MD.	The value is a string of 1 to 43 case-sensitive characters without spaces, hyphens (-), and question marks (?). NOTE: When double quotation marks are used around the string, spaces are allowed in the string.
ma ma-name	Specifies the name of an MA.	The value is a string of 1 to 43 case-sensitive characters without spaces, hyphens (-), and question marks (?). The total length of the names of the MA and MD must be within 44 characters. NOTE: When double quotation marks are used around the string, spaces are allowed in the string.
mac mac-address	Specifies the MAC address of the destination node. The destination node can be a MEP or MIP. mac-address specifies the MP's MAC address. The value is in H-H-H format. An H is a hexadecimal number of 1 to 4 digits. The value cannot be a broadcast or multicast MAC address. NOTE: An MP's MAC address can be a bridge MAC address or the MAC address of the interface where the MP is configured. The MAC address depends on the configured MP address model: If the shared MP address model is configured, an MP uses a bridge MAC address as its own MAC address. If the independent MP address model is configured, an MP uses the MAC address of the interface where the MP is configured.	-
remote-mep mep-id mep-id	Specifies the ID of an RMEP.	The value is an integer that ranges from 1 to 8191.
interface-type interface-number	Specifies the outbound interface on the local device for sending LTMs. interface-type specifies the interface type. interface-number specifies the interface number. This parameter must be specified if the forwarding entry of the destination node does not exist in the MAC address table or there is more than one interface in a VLAN.	-
-t timeout	Specifies the timeout interval for waiting for an LTR messages.	The value is an integer that ranges from 1 to 65535, in milliseconds. The default value is 2000 ms.
ttl ttl	Specifies the maximum hop of LTMs.	The value is an integer that ranges from 1 to 255. The default value is 64.

Views

All views

Default Level

0: Visit level

Usage Guidelines

Usage Scenario

Similar to traceroute (tracert for short), 802.1ag MAC trace tests the path between the local device and the destination device or locates failure points by sending test packets and receiving reply packets.

A device is usually configured with multiple MDs and MAs. To locate failure points or detect connectivity of a link between one MEP to another MEP or a MIP in the same MA, perform either of the following operations:

Run the trace mac-8021ag command in the MA view.
- Run the trace mac-8021ag command without md md-name and ma ma-name specified to test the actual forwarding patch and locate failure points in a specified MA.
- Run the md md-name ma ma-name command with md md-name and ma ma-name specified to test the actual forwarding patch and locate failure points based on the configured MA and MD.
Run the trace mac-8021ag md md-name ma ma-name command in all views except the MA view to test the actual forwarding patch and locate failure points based on the configured MA and MD.

Prerequisites

The MA has been associated with a VLAN.
The MEP has been configured in the MA.

Precautions

A MEP initiates an 802.1ag MAC trace test to monitor reachability of the MEP's or MIP's destination address. These nodes have the same level and can be located in the same MA or different MAs.

If the outbound interface is specified, it cannot be configured with an inward-facing MEP.

Example

# Trace the MEP with the MAC address of aa99-6600-5600 from the MEP in the MA macustomer, with the TTL of 64.

<HUAWEI> system-view
[HUAWEI] cfm enable
[HUAWEI] cfm md mdcustomer
[HUAWEI-md-mdcustomer] ma macustomer
[HUAWEI-md-mdcustomer-ma-macustomer] trace mac-8021ag mep mep-id 1 mac aa99-6600-5600 ttl 64

Tracing the route to aa99-6600-5600 over a maximum of 64 hops:
-----------------------------------------------------------------------------
 Hops  Ingress Mac        Ingress Port              Ingress Action      Relay Action
       Egress Mac         Egress Port               Egress Action       Ismep
------------------------------------------------------------------------------
1       2155-2201-3302     Vlanif0/0/1     IngOK               RlyFDB       
        0018-82e2-36db     Vlanif0/0/1     EgrOK               NoMep

**Table 1** Description of the **trace mac-8021ag** command output
Item	Description
Hops	Number of hops.
Ingress Mac	MAC address of the inbound interface for receiving LTMs on the intermediate node or destination node.
Ingress Port	Inbound interface for receiving LTMs on the intermediate node or destination node.
Ingress Action	Action taken by the inbound interface to process LTMs: IngOK: The inbound interface forwards LTMs successfully. If this field is empty, the inbound interface fails to forward LTMs.
Reply Action	Action taken by the device to process LTMs: RlyFDB: The device forwards LTMs to the next hop device. RlyHit: The device forwards LTMs to the destination device.
Egress Mac	MAC address of the outbound interface for forwarding LTMs on the intermediate node.
Egress Port	Outbound interface for forwarding LTMs on the intermediate node.
Egress Action	Action taken by the outbound interface to process LTMs: EgrOK: The outbound interface forwards LTMs successfully. If this field is empty, the outbound interface does not or fails to forward LTMs.
Ismep	Whether the mode of the outbound interface is a MEP: NoMep IsMep