ping meg ttl

Function

The ping meg ttl command enables the loopback function to monitor the connectivity of an MPLS-TP link in a specified MEG.

Format

ping meg meg-name ttl ttl-number [ -c count-value | packet-size size-value | -t timeout-value ] ^* [ request-tlv ]

Parameters

Parameter	Description	Value
meg-name	Specifies the name of a MEG.	The value is a string of 1 to 14 case-sensitive characters, spaces not supported.
ttl ttl-number	Specifies the number of hops of the route to the destination of a probe packet.	The value is an integer ranging from 1 to 255. The default value is 255.
-c count-value	Specifies the number of sent probe packets.	The value is an integer ranging from 1 to 268435455. The default value is 5.
packet-size size-value	Specifies the size of a ping packet.	The value is an integer ranging from 64 to 1500.
-t timeout-value	Specifies the timeout period for waiting for a response packet, in milliseconds.	The value is an integer ranging from 1 to 65535, in milliseconds. The default value is 2000.
request-tlv	Specifies the request type-length-value (TLV).	-

Views

All views

Default Level

0: Visit level

Task Name and Operations

Task Name	Operations
tpoam	execute

Usage Guidelines

Usage Scenario

The ping meg ttl command is the most common tool that is used to test MPLS-TP network connectivity. It uses loopback packets to monitor:

Availability of a remote device
Round-trip delay in communication between MEPs
Loss of ping packets
After the ping meg ttl command is run on a MEP to monitor bidirectional link connectivity, the MEP sends a unicast ETH-LB frame carrying a request. If no reply to the unicast ETH-LB frame is received within an interval specified by timeout-value, the link between the MEP and RMEP is considered disconnected.
If the network speed is slow, set the timeout-value parameter to a large value in the ping meg ttl command.

Prerequisites

A MEG and an ME have been created.
An ME has been created on the MIP for ping MIP. Ping MIP can be initiated only on a MEP. A MIP can only respond to packets from the MEP and cannot be an initiator.

Precautions

If the transmission speed is slow, increase the timeout period to wait for a response packet.

Ping MIP can monitor static bidirectional co-routed LSPs and multi-segment PWs only.

Example

# Enable the loopback function to monitor the connectivity of the link in a MEG named test with ttl value 16.

[~HUAWEI] ping meg test ttl 16
  PING test: 128 data bytes, press CTRL_C to break
    Reply from test: bytes=128, Sequence=2 time=261 ms
    Reply from test: bytes=128, Sequence=3 time=8 ms
    Reply from test: bytes=128, Sequence=4 time=8 ms
    Request time out, Sequence = 1
    Reply from test: bytes=128, Sequence=5 time=11 ms
  --- ping statistics ---
    5 packet(s) transmitted
    4 packet(s) received
    20.00% packet loss
    round-trip min/avg/max 8/72/261 ms