Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

Navigation

Example: Configuring One-Way Ethernet Frame Delay Measurements with Single-Tagged Interfaces

This example uses two MX Series routers: MX-1 and MX-2. The configuration creates a CFM down MEP session on a VLAN-tagged logical interface connecting the two (ge-5/2/9 on Router MX-1 and ge-0/2/5 on Router MX-2).

Note: These are not complete router configurations.

Configuration on Router MX-1:

[edit]interfaces {ge-5/2/9 {vlan-tagging;unit 0 {vlan-id 512;}}}protocols {oam {ethernet {connectivity-fault-management {traceoptions {file eoam_cfm.log size 1g files 2 world-readable;flag all;}linktrace {path-database-size 255;age 10s;}maintenance-domain md6 {level 6;maintenance-association ma6 {continuity-check {interval 100ms;hold-interval 1;}mep 201 {interface ge-5/2/9.0;direction down;auto-discovery;}}}}}}}

Configuration on Router MX-2:

[edit]interfaces {ge-0/2/5 {vlan-tagging;unit 0 {vlan-id 512;}}}protocols {oam {ethernet {connectivity-fault-management {traceoptions {file eoam_cfm.log size 1g files 2 world-readable;flag all;}linktrace {path-database-size 255;age 10s;}maintenance-domain md6 {level 6;maintenance-association ma6 {continuity-check {interval 100ms;hold-interval 1;}mep 101 {interface ge-0/2/5.0;direction down;auto-discovery;}}}}}}}

From Router MX-2, start a one-way delay measurement to Router MX-1.

user@MX-2> monitor ethernet delay-measurement one-way mep 201 maintenance-domain md6 maintenance-association ma6 count 10
One-way ETH-DM request to 00:90:69:0a:43:94, Interface ge-0/2/5.0
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

The counters are displayed as part of the local MEP database on Router MX-2.

user@MX-2> show oam ethernet connectivity-fault-management mep-database maintenance-domain md6 maintenance-domain ma6
Maintenance domain name: md6, Format: string, Level: 6
  Maintenance association name: ma6, Format: string
  Continuity-check status: enabled, Interval: 100ms, Loss-threshold: 3 frames
  MEP identifier: 101, Direction: down, MAC address: 00:90:69:0a:48:57
  Auto-discovery: enabled, Priority: 0
  Interface name: ge-0/2/5.0, Interface status: Active, Link status: Up
  Defects:
    Remote MEP not receiving CCM                  : no
    Erroneous CCM received                        : no
    Cross-connect CCM received                    : no
    RDI sent by some MEP                          : no
  Statistics:
    CCMs sent                                     : 1590
    CCMs received out of sequence                 : 0
    LBMs sent                                     : 0
    Valid in-order LBRs received                  : 0
    Valid out-of-order LBRs received              : 0
    LBRs received with corrupted data             : 0
    LBRs sent                                     : 0
    LTMs sent                                     : 0
    LTMs received                                 : 0
    LTRs sent                                     : 0
    LTRs received                                 : 0
    Sequence number of next LTM request           : 0
    1DMs sent                                     : 10
    Valid 1DMs received                           : 0
    Invalid 1DMs received                         : 0
    DMMs sent                                     : 0
    DMRs sent                                     : 0
    Valid DMRs received                           : 0
    Invalid DMRs received                         : 0
  Remote MEP count: 1
    Identifier    MAC address        State    Interface
      201     00:90:69:0a:43:94       ok    ge-0/2/5.0

The remote MEP database statistics are available on Router MX-1.

user@MX-1> show oam ethernet connectivity-fault-management mep-database maintenance-domain md6
Maintenance domain name: md6, Format: string, Level: 6
  Maintenance association name: ma6, Format: string
  Continuity-check status: enabled, Interval: 100ms, Loss-threshold: 3 frames
  MEP identifier: 201, Direction: down, MAC address: 00:90:69:0a:43:94
  Auto-discovery: enabled, Priority: 0
  Interface name: ge-5/2/9.0, Interface status: Active, Link status: Up
  Defects:
    Remote MEP not receiving CCM                  : no
    Erroneous CCM received                        : no
    Cross-connect CCM received                    : no
    RDI sent by some MEP                          : no
  Statistics:
    CCMs sent                                     : 1572
    CCMs received out of sequence                 : 0
    LBMs sent                                     : 0
    Valid in-order LBRs received                  : 0
    Valid out-of-order LBRs received              : 0
    LBRs received with corrupted data             : 0
    LBRs sent                                     : 0
    LTMs sent                                     : 0
    LTMs received                                 : 0
    LTRs sent                                     : 0
    LTRs received                                 : 0
    Sequence number of next LTM request           : 0
    1DMs sent                                     : 0
    Valid 1DMs received                           : 10
    Invalid 1DMs received                         : 0
    DMMs sent                                     : 0
    DMRs sent                                     : 0
    Valid DMRs received                           : 0
    Invalid DMRs received                         : 0
  Remote MEP count: 1
    Identifier    MAC address        State    Interface
      101     00:90:69:0a:48:57       ok    ge-5/2/9.0

The remote Router MX-1 should also collect the delay statistics (up to 100 per session) for display with mep-statistics or delay-statistics.

user@MX-1> show oam ethernet connectivity-fault-management mep-statistics maintenance-domain md6
MEP identifier: 201, MAC address: 00:90:69:0a:43:94
Remote MEP count: 1
  CCMs sent                                     : 3240
  CCMs received out of sequence                 : 0
  LBMs sent                                     : 0
  Valid in-order LBRs received                  : 0
  Valid out-of-order LBRs received              : 0
  LBRs received with corrupted data             : 0
  LBRs sent                                     : 0
  LTMs sent                                     : 0
  LTMs received                                 : 0
  LTRs sent                                     : 0
  LTRs received                                 : 0
  Sequence number of next LTM request           : 0
  1DMs sent                                     : 0
  Valid 1DMs received                           : 10
  Invalid 1DMs received                         : 0
  DMMs sent                                     : 0
  DMRs sent                                     : 0
  Valid DMRs received                           : 0
  Invalid DMRs received                         : 0

  Remote MEP identifier: 101
  Remote MAC address: 00:90:69:0a:48:57
    Delay measurement statistics:
    Index  One-way delay  Two-way delay
              (usec)         (usec)    
      1        370          
      2        357          
      3        344          
      4        332          
      5        319          
      6        306          
      7        294          
      8        281          
      9        269          
      10       255          
    Average one-way delay          : 312 usec
    Average one-way delay variation: 11 usec
    Best case one-way delay        : 255 usec
    Worst case one-way delay       : 370 usec
user@MX-1> show oam ethernet connectivity-fault-management delay-statistics maintenance-domain md6
MEP identifier: 201, MAC address: 00:90:69:0a:43:94
Remote MEP count: 1

  Remote MAC address: 00:90:69:0a:48:57
    Delay measurement statistics:
    Index  One-way delay  Two-way delay
              (usec)         (usec)    
      1        370          
      2        357          
      3        344          
      4        332          
      5        319          
      6        306          
      7        294          
      8        281          
      9        269          
      10       255          
    Average one-way delay          : 312 usec
    Average one-way delay variation: 11 usec
    Best case one-way delay        : 255 usec

Note: When two systems are close to each other, their one-way delay values are very high compared to their two-way delay values. This is because one-way delay measurement requires the timing for the two systems to be synchronized at a very granular level and MX Series routers do not support this granular synchronization. However, two-way delay measurement does not require synchronized timing, making two-way delay measurements more accurate.

Published: 2012-11-26