monitor ethernet synthetic-loss-measurement

Syntax

Description

(MX Series routers) Start an ITU-T Y.1731 Ethernet synthetic loss measurement (ETH-SLM) session between the specified local connectivity fault management (CFM) maintenance association end point (MEP) and the specified remote MEP, and display a summary of the frames exchanged in the measurement session. ETH-SLM (also called synthetic frame loss measurement) statistics are stored at one of the MEPs for later retrieval.

Note:

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

To start an Ethernet synthetic frame loss measurement session, the router initiates an exchange of frames carrying synthetic frame loss measurement protocol data units (PDUs) between the local and remote MEPs. The frame counts—the types of and number of Ethernet synthetic frame loss measurement PDU frames exchanged to measure frame delay times—are displayed as the run-time output of the monitor ethernet synthetic-loss-measurement command and are also stored at both the initiator and receiver MEPs for later retrieval. Ethernet synthetic frame loss measurement statistics, described below, are measured and stored at only one of the MEPs:

Frame delay—The difference, in microseconds, between the time a frame is sent and when it is received.

Frame delay variation—The difference, in microseconds, between consecutive frame delay values. Frame delay variation is sometimes called “frame jitter.”

Options

maintenance-domain `md-name`	Name of an existing CFM maintenance domain.
maintenance-association `ma-name`	Name of an existing CFM maintenance association.
mep `remote-mep-id`	Numeric identifier of the peer MEP with which to perform Ethernet synthetic frame loss measurement. The discovered MAC address of the peer MEP is used. The range of values is from 1 through 8191.
`remote-mac-address`	Unicast MAC address of the peer MEP with which to perform Ethernet synthetic 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 65,535 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-milliseconds`	(Optional) Number of milliseconds to wait between sending frames. You must specify this value in multiples of 100 milliseconds. The range of values is from 100 through 50000 milliseconds. The default value is 100 milliseconds.
priority `802.1p value`	(Optional) Priority of the ETH-SLM request frame supported. The range of values is from 0 through 7. The default value is zero.
size	(Optional) Size of the data TLV to be included in the request frame. The range of values is from 1 through 1400 bytes.
xml	(Optional) Allow the output of the command to be displayed in XML format for ETH-SLM. Note that the only way to get output in XML format is to use the `xml` argument. The `display xml` command does not work.

Additional Information

To display the frame counts collected at a MEP as the result of this command, use the following commands as described in the CLI Explorer:

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 a MEP as the result of this command, use the following commands as described in the CLI Explorer.

show oam ethernet connectivity-fault-management synthetic-loss-measurement
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 statistics command, described in the CLI Explorer.

For a complete description of Ethernet synthetic 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

Output Fields

The monitor ethernet synthetic-loss-measurement command displays different output at the CLI, depending on when you start a synthetic frame loss measurement:

Table 1 lists the run-time output fields for the monitor ethernet synthetic-loss-measurement command.

Output fields are listed in the approximate order in which they appear.

Table 1: monitor ethernet synthetic-loss-measurement Output Fields
Output Field Name	Output Field Description
`ETH-SLM 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.
`SLM packets sent`	Total number of synthetic loss message (SLM) PDU frames sent from the source MEP to the remote MEP during this ETH-SLM session.
`SLR packets received`	Total number of synthetic loss reply (SLR) PDU frames received by the source MEP from the remote MEP during this measurement session.
`Local TXFC1 value`	Number of synthetic frames transmitted to the peer MEP for a test ID. A test ID is used to distinguish each synthetic loss measurement because multiple measurements can be simultaneously activated also on a given CoS and MEP pair. It must be unique at least within the context of any SLM for the MEG and initiating MEP.
`Local RXFC1 value`	Number of synthetic frames received from the peer MEP for a test ID. The MEP generates a unique test ID for the session, adds the source MEP ID, and initializes the local counters for the session before SLM initiation. For each SLM PDU transmitted for the session (test ID), the local counter TXFC1 is sent in the packet.
`Last Received SLR frame TXFCf(tc)`	Value of the local counter TxFCl at the time of SLM frame transmission.
`Last Received SLR frame TXFCb(t`	Value of the local counter RxFCl at the time of SLR frame transmission.
`Frame loss (near-end)`	Count of frame loss associated with ingress data frames.
`Frame loss (far-end)`	Count of frame loss associated with egress data frames.

Sample Output