Using Tracert to Test the Forwarding Path on a PWE3 Network

You can run the tracert command to obtain information about the SPEs and Ps through which packets pass from the source to the destination. Based on the command output, you can monitor PW connectivity and locate faulty nodes.

Context

Perform the following steps on the PE of a PWE3 network:

Procedure

To locate the faulty node on a PWE3 network, run any of the following commands as required:
- To monitor connectivity of the PWE3 network through the control word channel, run:
  
  tracert vc vc-type pw-id [ peer-address ] [ -exp exp-value | -f first-ttl | -m max-ttl | -r reply-mode | -t timeout-value | -g ] ^* control-word [ ptn-mode | full-lsp-path ] [ pipe | uniform ] [ detail ]
  
  tracert vc vc-type pw-id [ peer-address ] [ -exp exp-value | -f first-ttl | -m max-ttl | -r reply-mode | -t timeout-value | -g ] ^* control-word remote remote-ip-address [ ptn-mode | full-lsp-path ] [ pipe | uniform ] [ detail ] [ bypass -si interface-name | interface-type interface-number ]
- To monitor connectivity of the PWE3 network through the label alert channel, run:
  
  tracert vc vc-type pw-id [ peer-address ] [ -exp exp-value | -f first-ttl | -m max-ttl | -r reply-mode | -t timeout-value | -g ] ^* label-alert [ no-control-word ] [ full-lsp-path ] [ pipe | uniform ] [ detail ] [ bypass -si interface-name | interface-type interface-number ]
- To monitor check connectivity of the PWE3 network in ordinary mode, run:
  
  tracert vc vc-type pw-id [ peer-address ] [ -exp exp-value | -f first-ttl | -m max-ttl | -r reply-mode | -t timeout-value | -g ] * normal [ remote remote-ip-address ] } [ full-lsp-path ] [ pipe | uniform ] [ detail ] [ bypass -si interface-name | interface-type interface-number ]
Before using the tracert vc command to monitor PWE3 network connectivity, perform the following operations:
- Configure the PWE3 network correctly.
- If the control word channel is used, run the control-word command in the PW template view to enable the control word function.
```
<HUAWEI> tracert vc vlan 100 control-word remote 4.1.1.2 full-lsp-path
  TTL   Replier            Time    Type      Downstream
  0                                Ingress   1.1.1.2/[1025 ]
  1     1.1.1.2           230 ms  Transit    2.1.1.2/[1301 ]
  2     2.1.1.2           230 ms  Transit    3.1.1.2/[1208 ]
  3     3.1.1.2           100 ms  Transit    4.1.1.2/[3 ]
  4     4.1.1.2           150 ms  Egress
```
The preceding command output contains information about each node along the PW and the response time of each hop.