PCMD record generation

The MAG-c supports PCMD record configuration using CLI commands. A PCMD record is streamed to the provisioned real-time port when the record is created.

Configuring the destination port for PCMD records

The MAG-c collects and streams session PCMD records. Use the following command to configure the destination port for PCMD records:

configure mobile-gateway profile pcmd destination port

Session records

Session records overview

The most important entity reported in the PCMD session records is a procedure that describes the event (for example, attach, detach, PDU session create, modify bearer, and QoS flow modification). A procedure contains a set of messages that are reported together. A specific message starts a procedure and another message ends it. However, some exception procedures, such as session deletion because of MME failure, are initiated internally by the system without requiring an external trigger message. A procedure can also be relevant to bearers that are reported with it.

If a procedure starts while another procedure is still ongoing, the procedures are reported together as concurrent procedures. A procedure is concurrent if it is relevant to some bearers in the original procedure.

For example, when DL packets are received for an idle UE for a specific default bearer, a paging procedure is triggered and the DDN is sent to the MME. At the same time, the MME sends a Delete Session Request for this default bearer.

A session PCMD record is created when any of the supported 3GPP procedures are triggered and the call flow of the procedure ends (normally or abnormally).

Each session PCMD record contains fields for subscriber information (IMSI, SUPI, MSISDN, GPSI, IMEI, PEI), procedure ID, procedure result, procedure failure cause, and other data relevant to the procedure, such as bearer ID, QoS flow ID, APN, and slice.

Session record verbosity

The session PCMD can include either of the following records:
  • The standard record contains only the mandatory and conditional fields.
  • The extended record contains mandatory and conditional fields plus optional and conditional-optional fields.

Mandatory fields are always present. Optional fields are present only when an extended record is generated. Conditional (and conditional-optional) fields are filled in the PCMD record if the related information elements (IEs) are present in the signaling messages involved in the procedure. In some cases, a conditional parameter may be filled in the PCMD record even when the IE is not present in any signaling message. This happens when the MAG-c processing function knows the value, for example, through state information kept from previous processing.

The descriptions in the IE indicate the presence or availability of each PCMD IE; see PCMD record information elements for more information about IEs.

The procedure result and the configured verbosity type determine the type of PCMD records that are generated and streamed. Use the following CLI command to configure the verbosity type:

configure mobile-gateway profile pcmd session-report verbosity
The possible values for the verbosity are:
  • failure-only
  • standard
  • extended

The following table lists the triggers for creating PCMD session records.

Table 1. Triggers for the creation of PCMD session records
User setting (CLI) verbosity command Records
Extended session PCMD record for result FAILURE Standard session PCMD record for result NORMAL Extended session PCMD record for result NORMAL
failure-only X

—

—
standard X X

—

extended

 X

—

X

See Session PCMD record format for more information about the container formats that construct the standard and the extended session PCMD records.

See Generating and transmitting PCMD records for more information about generating and transmitting PCMD records.

PCMD heartbeat messages

The PCMD interface sends periodic heartbeat messages to notify the collector that the MAG-c reporting application is alive. This is especially useful in silent periods, for example, during the integration phase or when traffic is low.

The MAG-c active OAM‑VM transmits the heartbeat messages toward the configured PCMD destination, based on the configuration in the PCMD profile. Use the following CLI command to modify the default setting for the heartbeat messages. 
configure mobile-gateway profile pcmd heartbeat

See Generating and transmitting PCMD records for more information about configuring the PCMD profile.

Generating and transmitting PCMD records

An internal process collects PCMD data and generates the PCMD records. When a user configures a PCMD profile and assigns it to a PDN, the internal process starts generating (not transmitting) PCMD records. To transmit the generated PCMD records, the user must also configure the PCMD profile with a reachable destination IP address and assign it to a PDN that is operationally enabled.

PCMD records start generating as soon as you associate a PCMD profile with a PDN, regardless of whether you configure a reachable destination IP address.
Note: Generating PCMD records can have a performance impact on the system, regardless of whether the PCMD records are transmitted.

To transmit the generated PCMD records, the following is required:

  • Configure the PCMD profile with a reachable destination IP address.
  • Assign the PCMD profile to a PDN that is operationally enabled (no shutdown command).
Note:
  • Reachability is calculated based on the local routing information and the link status. As a result, the MAG-c starts and stops PCMD record transmission and accordingly updates the PCMD operational state based on network configuration and interface status only.

  • The PCMD transmission stops with any of the following events:

    • You execute the shutdown command at the PDN to shutdown the PDN.

    • You execute the no pcmd command at the PDN to disable the PCMD profile.

    • Connectivity to the configured destination IP address fails and the destination becomes unreachable.

In the following procedure, the PCMD profile configuration settings are defined as follows:

  • The profile name is PCMD-records.

  • The PCMD network destination is 192.0.2.2.

  • The session report verbosity type is extended.

  1. Configure a PCMD profile.
    Note: If you are modifying the configuration of a PCMD profile that is already assigned to the PDN, remove the profile from the PDN configuration before making the changes. The MAG-c does not support configuration of the PCMD profile while it is assigned to the PDN.
    configure mobile-gateway profile pcmd
    configure mobile-gateway profile pcmd PCMD-records
  2. Configure the network destination for the PCMD profile records.

    PCMD records generate without a configured network destination, however a reachable destination IP address is required to transmit the generated PCMD records.

    configure mobile-gateway profile pcmd destination
    configure mobile-gateway profile pcmd PCMD-records destination 192.0.2.2
  3. Optional: Modify the default report type for the PCMD profile. 
    configure mobile-gateway profile pcmd session-report verbosity
    configure mobile-gateway profile pcmd PCMD-records session-report verbosity extended
  4. Optional: Modify the default periodic heartbeat transmission in the PCMD interface. 
    configure mobile-gateway profile pcmd heartbeat
    configure mobile-gateway profile pcmd PCMD-records heartbeat 15
  5. Assign the PCMD profile to the gateway instance. 
    configure mobile-gateway pdn pcmd profile
    configure mobile-gateway pdn 1 pcmd profile PCMD-records
  6. Ensure the PDN is in the operationally enabled state. 
    configure mobile-gateway pdn 1 no shutdown
  7. View the PCMD configuration. 
    show mobile-gateway profile pcmd                                                             
    show mobile-gateway profile pcmd PCMD-records
    A:MAG-c# show mobile-gateway profile pcmd "PCMD-records"
===============================================================================
PCMD profile
===============================================================================
Profile name        : PCMD-records
Description         : none
Destination address : 192.0.2.2
Destination port    : 29780
Destination router  : Base
Heartbeat           : 15
Session Report:
Verbosity           : extended
-------------------------------------------------------------------------------
Number of profiles  : 1
===============================================================================
  8. View the PCMD statistics. 
    show mobile-gateway pdn pcmd-stats
    A:MAG-c# show mobile-gateway pdn pcmd-stats
===============================================================================
PDN gateway PCMD statistics
===============================================================================
VNF/VM           : 1/3                  Gateway          : 1

PDN PCMD Profile name     : PCMD-records
PDN PCMD Profile duration : 0d 00:04:37
PDN PCMD oper. state      : up

Session records
---------------
Success records  : 0
Failure records  : 0
Success extended : 3
Success limited  : 0
Total records    : 3
Total bytes      : 588

---------------------------
Gateway lifetime statistics
---------------------------
Success records  : 3                    Failure records  : 0
-------------------------------------------------------------------------------
Number of cards  : 1
-------------------------------------------------------------------------------
NOTE: Gateway lifetime statistics represent all generated session records count
      since gateway creation regardless profile is assigned to gateway or not.
===============================================================================