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    monitor ethernet delay-measurement

    Syntax

    monitor ethernet delay-measurement maintenance-domain md-name maintenance-association ma-name (one-way | two-way) (remote-mac-address | mep remote-mep-id) <count count> <no-session-id-tlv> <priority 802.1p value> <size size> <wait time>

    Release Information

    Command introduced in Junos OS Release 11.4 for EX Series switches.

    Description

    Start an ITU-T Y.1731 Ethernet frame delay measurement 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. Frame delay 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 type Ctrl +C to explicitly quit the monitor ethernet delay-measurement command and return to the CLI command prompt.

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

    For one-way Ethernet frame delay measurement, only the receiver MEP (on the remote system) collects statistics. For two-way Ethernet frame delay measurement, only the initiator MEP (on the local system) collects statistics.

    Options

    count count

    (Optional) Number of frames to send to the specified peer MEP. The range of values is 1 through 65,535 frames. The default value is 10 frames.

    maintenance-association ma-name

    Name of an existing CFM maintenance association.

    maintenance-domain md-name

    Name of an existing CFM maintenance domain.

    mep remote-mep-id

    Numeric identifier of the peer MEP with which to perform Ethernet frame delay measurement. The discovered MAC address of the peer MEP is used. The range of values is 1 through 8191.

    no-session-id-tlv

    (Optional) Prevent insertion of the session ID TLV in the request frame.

    one-way

    Measurement type is one-way Ethernet frame delay measurement, which is based on the difference between the time at which the initiator MEP sends a one-way delay measurement request (1DM) frame and the time at which the receiver MEP receives the frame.

    priority 802.1p value

    (Optional) Priority of the delay measurement request frame supported by both one-way delay measurement and two-way delay measurement. The range of values is from 0 through 7. The default value is zero.

    remote-mac-address

    Unicast MAC address of the peer MEP with which to perform Ethernet frame delay measurement. Specify the MAC address as six hexadecimal bytes in nn:nn:nn:nn:nn:nn format. Multicast MAC addresses are not supported.

    size size

    (Optional) Size of the data TLV to be included in the request frame. The range of values is from 1 through 1400 bytes.

    two-way

    Measurement type is two-way Ethernet frame delay measurement, which is based on the difference between the time at which the initiator MEP sends a two-way delay measurement message (DMM) frame and the time at which the initiator MEP receives an associated two-way delay measurement reply (DMR) frame from the responder MEP, subtracting the time elapsed at the responder MEP.

    wait time

    (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.

    Required Privilege Level

    trace and maintenance

    List of Sample Output

    monitor ethernet delay-measurement one-way
    monitor ethernet delay-measurement two-way
    monitor ethernet delay-measurement two-way (Invalid DMR Frames Received)

    Output Fields

    The monitor ethernet delay-measurement command displays different output at the CLI, depending on whether you start a one-way or two-way frame delay measurement:

    • Table 1 lists the run-time output fields for the monitor ethernet delay-measurement one-way command.
    • Table 2 lists the run-time output fields for the monitor ethernet delay-measurement two-way command.

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

    Table 1: monitor ethernet delay-measurement one-way Output Fields

    Output Field Name

    Output Field Description

    One-way ETH-DM 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.

    1DM Frames sent

    PDU frames sent to the remote MEP in this ETH-DM session.

    Packets transmitted

    Total number of 1DM PDU frames sent to the remote MEP during this measurement session.

    Average delay

    Average two-way frame delay measured in this session.

    Average delay variation

    Average frame jitter measured in this session.

    Best case delay

    Lowest two-way frame delay measured in this session.

    Worst case delay

    Highest two-way frame delay measured in this session.

    Note: For one-way delay measurement, these CLI output fields display NA (“not applicable”) at the initiator MEP because one-way frame delay measurements occur at the receiver MEP.

    Table 2: monitor ethernet delay-measurement two-way Output Fields

    Output Field Name

    Output Field Description

    Two-way Ethernet frame 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.

    DMR received from

    Unicast MAC address of the remote MEP that transmitted this DMR frame in response to a DMM frame.

    Delay

    Two-way delay, in microseconds, for the initiator-transmitted DMM frame.

    Delay variation

    Difference, in microseconds, between the current and previous delay values. This is also known as jitter.

    Packets transmitted

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

    Valid packets received

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

    Average delay

    Average two-way frame delay measured in this session.

    Average delay variation

    Average frame jitter measured in this session.

    Best case delay

    Lowest two-way frame delay measured in this session.

    Worst case delay

    Highest two-way frame delay measured in this session.

    Sample Output

    monitor ethernet delay-measurement one-way

    user@switch> monitor ethernet delay-measurement one-way 00:05:85:73:39:4a maintenance-domain md6 maintenance-association ma6 count 10
    One-way ETH-DM request to 00:05:85:73:39:4a, Interface xe-5/0/0.0
    1DM Frames sent : 10
    --- Delay measurement statistics ---
    Packets transmitted: 10
    Average delay: NA, Average delay variation: NA
    Best case delay: NA, Worst case delay: NA
    

    monitor ethernet delay-measurement two-way

    user@switch> monitor ethernet delay-measurement two-way 00:05:85:73:39:4a maintenance-domain md6 maintenance-association ma6 count 10
    Two-way ETH-DM request to 00:05:85:73:39:4a, Interface xe-5/0/0.0
    DMR received from 00:05:85:73:39:4a  Delay: 100 usec  Delay variation: 0 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 8 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 0 usec
    DMR received from 00:05:85:73:39:4a  Delay: 111 usec  Delay variation: 19 usec
    DMR received from 00:05:85:73:39:4a  Delay: 110 usec  Delay variation: 1 usec
    DMR received from 00:05:85:73:39:4a  Delay: 119 usec  Delay variation: 9 usec
    DMR received from 00:05:85:73:39:4a  Delay: 122 usec  Delay variation: 3 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 30 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 0 usec
    DMR received from 00:05:85:73:39:4a  Delay: 108 usec  Delay variation: 16 usec
    
    --- Delay measurement statistics ---
    Packets transmitted: 10, Valid packets received: 10
    Average delay: 103 usec, Average delay variation: 8 usec
    Best case delay: 92 usec, Worst case delay: 122 usec
    

    monitor ethernet delay-measurement two-way (Invalid DMR Frames Received)

    user@switch> monitor ethernet delay-measurement two-way 00:05:85:73:39:4a maintenance-domain md6 maintenance-association ma6 count 10
    Two-way ETH-DM request to 00:05:85:73:39:4a, Interface xe-5/0/0.0
    DMR received from 00:05:85:73:39:4a  Delay: 100 usec  Delay variation: 0 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 8 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 0 usec
    DMR received from 00:05:85:73:39:4a  Delay: 111 usec  Delay variation: 19 usec
    DMR received from 00:05:85:73:39:4a  Delay: 110 usec  Delay variation: 1 usec
    DMR received from 00:05:85:73:39:4a  Delay: 119 usec  Delay variation: 9 usec
    DMR received from 00:05:85:73:39:4a  Delay: 122 usec  Delay variation: 3 usec
    DMR received from 00:05:85:73:39:4a  Delay: 92 usec   Delay variation: 30 usec
    DMR received from 00:05:85:73:39:4a with invalid timestamp(s).
    DMR received from 00:05:85:73:39:4a  Delay: 108 usec  Delay variation: 16 usec
    
    --- Delay measurement statistics ---
    Packets transmitted: 10, Valid packets received: 9, Invalid packets received: 1
    Average delay: 105 usec, Average delay variation: 9 usec
    Best case delay: 92 usec, Worst case delay: 122 usec
    

    Published: 2012-12-07