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Setting Up Link Trace Messages
- 25 Feb 2022
- 2 Minutes to read
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Setting Up Link Trace Messages
- Updated on 25 Feb 2022
- 2 Minutes to read
- Contributors
- Print
- PDF
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Link Trace Messages (LTM) are multicast frames transmitted by a MEP to track the path (hopby-hop) to a destination MEP. Each receiving MEP sends a trace route reply directly to the originating MEP, and regenerates the trace route message. LTM are discussed in IEEE 802.1ag.
▶ To start the link trace messages
Access the page SOAM ▶ CFM ▶ MEP ▶ LTM.
All existing link trace information for Maintenance association End Points is displayed.Click the MEPID of the MEP for which you want to start the LTM.
Complete the required fields, then click Start.
For more information on specific parameters, refer to the following tables.
MEP Link Trace (SOAM ▶ CFM ▶ MEP ▶ LTM)
| Parameter | Description |
|---|---|
| MEP Index Index | Index of the Maintenance association End Point |
| MEPID | Maintenance association End Point Identifier |
| Target Type | Link trace target by remote MEPID or MAC address. |
| Remote MEPID R-MEPID | Targeted remote MEPID. The remote MEP MAC address is resolved into the local MEP database. |
| LTR Received | The number of link trace responses received by this MEP |
| MAC Address | Target MAC address. Only unicast MAC addresses are valid for link trace target address. |
| TTL | Link trace time to live. Range: 0–255 If it is initially set to 0, no response should be received. |
| Set FDB Only Flag | Enables the LTM to set the flag "UseFDBonly" (IEEE 802.1ag) or the flag "HWonly" (Y.1731) |
Bottom of Table
| Parameter | Description |
|---|---|
| LTM Sequence Number Next Seq. # | Sequence number used by the latest link trace request initiated from that ME |
| Target MAC Address Target MAC | Target MAC address used by the latest link trace request |
| TTL | Link trace time to live received in link trace responses. |
| F | Forwarded. Indicates that the responder maintenance point did forward the LTM. |
| T | Terminal MEP. Indicates that the responder maintenance point is a MEP. |
| Action | Indicates how the responder system processes frames targeted for the destination address specified by the LTM Possible values are:
|
| TLV Type | Indicates which Type Length Values (TLVs) are included in link trace responses |
| TLV Value | The TLV values included in link trace responses |
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