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monitor ethernet loss-measurement

 

Syntax

Release Information

Command introduced in Junos OS Release 11.1.

local-mep option introduced in Junos OS Release 15.1

Description

Start an ITU-T Y.1731 Ethernet frame loss measurement session between the specified local connectivity fault management (CFM) maintenance association end point (MEP) and the specified remote MEP, and display a count of transmitted and received data frames between the pair of MEPs. Frame loss measurement statistics are stored at one of the MEPs for later retrieval. For MX Series routers, supports point-to-point down MEPs for Ethernet interfaces (as per IEEE 802.1ag over VPWS).

Note

If you attempt to monitor loss to a nonexistent MAC address, you must type Ctrl + c to explicitly quit the monitor ethernet loss-measurement command and return to the CLI command prompt.

To start an Ethernet frame loss measurement session, the router first sends frames with ETH-LM information to a peer MEP and similarly receives frames with ETH-LM information from the peer MEP. Frame loss is calculated by collecting the counter values applicable for ingress and egress service frames where the counters maintain a count of transmitted and received data frames between a pair of MEPs. The loss measurement statistics are retrieved as the output of the monitor ethernet loss-measurement command and are also stored at the initiator. The frames counts are stored at both the initiator and the receiver MEPs for later retrieval.

Options

maintenance-domain md-nameName of an existing CFM maintenance domain.
maintenance-association ma-nameName of an existing CFM maintenance association.
mep remote-mep-idNumeric identifier of the peer MEP with which to perform Ethernet frame loss measurement. The discovered MAC address of the peer MEP is used. The range of values is from 1 through 8192.
remote-mac-addressUnicast MAC address of the peer MEP with which to perform Ethernet frame loss measurement. Specify the MAC address as six hexadecimal bytes in one of the following formats: nnnn.nnnn.nnnn or nn:nn:nn:nn:nn:nn (for example, 0011.2233.4455 or 00:11:22:33:44:55). Multicast MAC addresses are not supported.
count frame-count(Optional) Number of frames to send to the specified peer MEP. The range of values is from 1 through 65535 frames. The default value is 10 frames.
local-mep mep-id(Required when multiple MEPs are configured) Identifier for the local maintenance endpoint.
wait interval-seconds(Optional) Number of seconds to wait between sending frames. The range of values is from 1 through 255 seconds. The default value is 1 second.
priority 802.1p value(Optional) Priority of the delay measurement request frame. The range of values is from 0 through 7. The default value is 1 second.
no-session-id-tlv(Optional) Disable the session id TLV argument set in the request frame.
xml(Optional) Allow the output of the command to be displayed in XML format.

Additional Information

To display the interator output for an LM session, run the following command:

  • show oam ethernet connectivity-fault-management sla-iterator-statistics sla-iterator <profile> maintenance-association <MA> maintenance-domain <MD> local-mep <MEP> remote-mep <RMEP>

To display the frame counts collected at an MEP as the result of this command, see the following command descriptions in the CLI Explorer:

  • show oam ethernet connectivity-fault-management loss-statistics

  • show oam ethernet connectivity-fault-management interfaces detail

  • show oam ethernet connectivity-fault-management mep-database

  • show oam ethernet connectivity-fault-management mep-statistics

To display the statistics collected at an MEP as the result of this command, see the following command descriptions in the CLI Explorer:

  • show oam ethernet connectivity-fault-management delay-statistics

  • show oam ethernet connectivity-fault-management mep-statistics

To clear both the frame counts and the statistics collected for MEPs, use the clear oam ethernet connectivity-fault-management loss-statistics maintenance-domain md-name maintenance-association ma-name command, as described in the CLI Explorer.

For a complete description of Ethernet frame loss measurement, see the ITU-T Y.1731 Ethernet Service OAM topics in the Junos OS Network Interfaces Library for Routing Devices.

Required Privilege Level

trace and maintenance

List of Sample Output

monitor ethernet loss-measurement

Output Fields

Table 1 lists the output fields for the monitor ethernet loss-measurement command and their descriptions. Output fields are listed in the approximate order in which they appear.

Table 1: monitor ethernet loss-measurement output fields

Output Field Name

Output Field Description

Ethernet loss delay measurement request to

Unicast MAC address of the remote peer MEP.

Interface

Name of the Ethernet physical, logical, or trunk interface to which the local MEP is attached.

LMR received from

Unicast MAC address of the remote MEP that transmitted this LMR frame in response to a loss measurement message (LMM) frame.

Near-end frame loss

Count of frame loss associated with ingress data frames.

Far-end frame loss

Count of frame loss associated with egress data frames.

Near-end loss ratio

Ratio, expressed as a percentage, of the number of service frames not delivered divided by the total number of service frames during time interval T at the ingress interface.

Far-end loss ratio

Ratio, expressed as a percentage, of the number of service frames not delivered divided by the total number of service frames during time interval T at the egress interface.

LMM packets transmitted

Total number of LMM PDU frames sent to the remote MEP in this measurement session.

LMR packets received

Total number of LMR PDU frames received from the remote MEP in this measurement session.

Average near-end frame loss

Average frame loss measured in this session associated with ingress data frames.

Average near-end loss ratio

Average frame loss ratio measured in this session associated with ingress data frames.

Average far-end frame loss

Average frame loss measured in this session associated with egress data frames.

Average far-end loss ratio

Average frame loss ratio measured in this session associated with egress data frames.

Near-end best case frame loss

Lowest frame loss measured in this session associated with ingress data frames.

Near-end best case loss ratio

Lowest frame loss ratio measured in this session associated with ingress data frames.

Near-end worst case frame loss

Highest frame loss measured in this session associated with ingress data frames.

Near-end worst case loss ratio

Highest frame loss ratio measured in this session associated with ingress data frames.

Far-end best case frame loss

Lowest frame loss measured in this session associated with egress data frames.

Far-end best case loss ratio

Lowest frame loss ratio measured in this session associated with egress data frames.

Far-end worst case frame loss

Highest frame loss measured in this session associated with egress data frames.

Far-end worst case loss ratio

Highest frame loss ratio measured in this session associated with egress data frames.

Note that in the preceding table, the term number of service frames not delivered is the difference between the number of service frames arriving at the ingress Ethernet flow point and the number of service frames delivered at the egress Ethernet flow point in a point-to-point Ethernet connection.

Sample Output

monitor ethernet loss-measurement

user@host> monitor ethernet loss-measurement mep 2 64:87:88:6a:da:94 maintenance-domain md maintenance-association ma count 10