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| Prolog Control Block Contents LCPDU DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

LCPDU Prolog | Top of page

     NAME       : HCPLCPDU
     DESCRIPTION: LinkAG LACP Protocol-Data-Unit (PDU) c/b
     DSECT      : LCPDU
     FUNCTION   : This control block maps the IEEE 802.3ad-2000
                  version 1 LACP PDU structure.
                  The Link Aggregation Control Protocol (LACP)
                  provides a standardized means for exchanging
                  information between Partner Systems on a link
                  to allow their Link Aggregation Control
                  instances to reach agreement on the identity
                  of the Link Aggregation Group to which the
                  link belongs, move the link to that Link
                  Aggregation Group, and enable its transmission
                  and reception functions in an orderly manner.
      Destination Address (DA):
        The DA in all LACP PDUs is the
        Slow_Protocols_Multicast address (01-80-C2-00-00-02).
      Source Address (SA):
        The SA in LACP PDU is the individual MAC address
        associated with the port from which the PDU is
        transmitted.
      Length/Type:
        LACP PDUs are always type encoded, and carry the Slow
        Protocol type field.  The encoding of this type field
        is 0x8809.
      Subtype:
        The Subtype field identifies the specific Slow
        Protocol being encapsulated.  LACP PDUs carry the
        carry the subtype value 0x01.
      Version number:
        This identifies the LACP protocol version;
        implementations conformant to IEEE 802.3ad of the
        standard carry the value 0x01.
      TLV_type = Actor Information:
        This field indicates the nature of the information
        carried in this TLVtuple.  Actor information is
        identified by the value 0x01.
      Actor_Information_Length:
        This field indicates the length (in bytes) of this
        TLV-tuple, Actor information uses a length value of 20
        (0x14).
      Actor_System_Priority:
        The priority assigned to this System (by management or
        administration policy), encoded as an unsigned
        integer.
      Actor_System:
        The Actor's System ID, encoded as a MAC address.
      Actor_Key:
        The operational Key value assigned to the port by the
        Actor, encoded as an unsigned integer.
      Actor_Port_Priority:
        The priority assigned to this port by the Actor (the
        System sending the PDU; assigned by management or
        administration policy), encoded as an unsigned
        integer.
      Actor_Port:
        The port number assigned to the port by the Actor (the
        System sending the PDU), encoded as an unsigned
        integer.
      Actor_State:
        The Actor's state variables for the port, encoded as
        individual bits within a single byte, as follows:
           1) LACP_Activity is encoded in bit 0. This flag
           indicates the Activity control value with regard to
           this link.  Active LACP is encoded as a 1; Passive
           LACP is encoded as a 0
           2) LACP_Timeout is encoded in bit 1. This flag
           indicates the Timeout control value with regard to
           this link.  Short Timeout is encoded as a 1; Long
           Timeout is encoded as a
           3) Aggregation is encoded in bit 2. If TRUE
           (encoded as a 1), this flag indicates that the
           System considers this link to be Aggregatable;
           i.e., a potential candidate for aggregation.  If
           FALSE (encoded as a 0), the link is considered to
           be Individual; i.e., this link can be operated only
           as an individual link.
           4) Synchronization is encoded in bit 3. If TRUE
           (encoded as a 1), the System considers this link to
           be IN_SYNC; i.e., it has been allocated to the
           correct Link Aggregation Group, the group has been
           associated with a compatible Aggregator, and the
           identity of the Link Aggregation Group is
           consistent with the System ID and operational Key
           information transmitted.  If FALSE (encoded as a
           0), then this link is currently OUT_OF_SYNC; i.e.,
           it is not in the right Aggregation.
           5) Collecting is encoded in bit 4. TRUE (encoded as
           a 1) means collection of incoming frames on this
           link is definitely enabled; i.e., collection is
           currently enabled and is not expected to be
           disabled in the absence of administrative changes
           or changes in received protocol information.  Its
           value is otherwise FALSE (encoded as a 0);
           6) Distributing is encoded in bit 5. FALSE (encoded
           as a 0) means distribution of outgoing frames on
           this link is definitely disabled; i.e.,
           distribution is currently disabled and is not
           expected to be enabled in the absence of
           administrative changes or changes in received
           protocol information.  Its value is otherwise TRUE
           (encoded as a 1);
           7) Defaulted is encoded in bit 6. If TRUE (encoded
           as a 1), this flag indicates that the Actor's
           Receive machine is using Defaulted operational
           Partner information, administratively configured
           for the Partner.  If FALSE (encoded as a 0), the
           operational Partner information in use has been
           received in a LACPDU;
           8) Expired is encoded in bit 7. If TRUE (encoded as
           a 1), this flag indicates that the Actor's Receive
           machine is in the EXPIRED state; if FALSE (encoded
           as a 0), this flag indicates that the Actor's
           Receive machine is not in the EXPIRED state.
           NOTE-The received values of Defaulted and Expired
           state are not used by LACP; however, knowing their
           values can be useful when diagnosing protocol
           problems.
      Reserved:
        These 3 bytes are reserved for use in future
        extensions to the protocol.  They shall be ignored on
        receipt and shall be transmitted as zeroes to claim
        compliance with Version 1 of this protocol.
      TLV_type = Partner Information:
        This field indicates the nature of the information
        carried in this TLV-tuple.  Partner information is
        identified by the integer value 0x02.
      Partner_Information_Length:
        This field indicates the length (in bytes) of this
        TLV-tuple, Partner information uses a length value of
        20 (0x14).
      Partner_System_Priority:
        The priority assigned to the Partner System (by
        management or administration policy), encoded as an
        unsigned integer.
      Partner_System:
        The Partner's System ID, encoded as a MAC address.
      Partner_Key:
        The operational Key value assigned to the port
        associated with this link by the Partner, encoded as
        an unsigned integer.
      Partner_Port_Priority:
        The priority assigned to this port by the Partner (by
        management or administration policy), encoded as an
        unsigned integer.
      Partner_Port:
        The port number associated with this link assigned to
        the port by the Partner, encoded as an unsigned
        integer.
      Partner_State:
        The Actor's view of the Partner's state variables,
        depicted in Figure 43-8 and encoded as individual bits
        within a single byte, as defined for Actor_State.
      Reserved:
        These 3 bytes are reserved for use in future
        extensions to the protocol.  They shall be ignored on
        receipt and shall be transmitted as zeroes to claim
        compliance with Version 1 of this protocol.
      TLV_type = Collector Information:
        This field indicates the nature of the information
        carried in this TLV-tuple.  Collector information is
        identified by the integer value 0x03
      Collector_Information_Length:
        This field indicates the length (in bytes) of this
        TLV-tuple.  Collector information uses a length value
        of 16 (0x10).
      CollectorMaxDelay:
        This field contains the value of Collector Maximum
        Delay of the station transmitting the LACPDU, encoded
        as an unsigned integer number of tens of microseconds.
        The range of values for this parameter is 0 to 65 535
        tens of microseconds (0.65535 seconds).
      Reserved:
        These 12 bytes are reserved for use in future
        extensions to the protocol.  They shall be ignored on
        receipt and shall be transmitted as zeroes to claim
        compliance with Version 1 of this protocol.
      TLV_type = Terminator:
        This field indicates the nature of the information
        carried in this TLV-tuple.  Terminator (end of
        message) information is identified by the integer
        value 0x00.
      Terminator_Length:
        This field indicates the length (in bytes) of this
        TLV-tuple.  Terminator information uses a length value
        of 0 (0x00).
      Reserved.:
        These 50 bytes are reserved for use in future
        extensions to the protocol.  They are ignored on
        receipt and are transmitted as zeroes to claim
        compliance with Version 1 of this protocol.
      FCS:
        This field is the Frame Check Sequence, typically
        generated by the underlying MAC.
        VM will create the packet without the FCS, as it
        will be added/removed by OSA.
     CREATED BY :
     DELETED BY :
      NCHORED   -
     RELOCATION CONSIDERATIONS : None

LCPDU Control Block Content | Top of page

     LCPDU DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      LCPDU          LinkAG LACP Protocol-Data-Unit (PDU) c/b
          Destination Address
    0000    0 Bitstring    6 LCPDEST        Destination Address
              0LCPDEST       LCPSPLAH       X'0180C200' LCPSPLAH
                                            Slow-Protocol-Multicast MSB
              .... ..1.      LCPSPLAL       X'0002' LCPSPLAL LSB Bytes
    0006    6 Bitstring    6 LCPSOURC       Source Address
    000C   12 Bitstring    4 LCPVID (0)     LACP PDU Verification Fields
    000C   12 Bitstring    2 LCPLEN         Length/Type Field
              00LCPLEN       LCPSPTF        X'8809' LCPSPTF
                                            Slow-Protocol-Type Field
    000E   14 Bitstring    1 LCPSTYPE       Slow Protocol Type
              .... ...1      LCPLACP        X'01' LCPLACP LinkAG Control
                                            Protocol(LACP)
    000F   15 Bitstring    1 LCPVER         LACP Protocol Version
              .... ...1      LCPVER1        X'01' LCPVER1 IEEE 802.3ab
                                            Version 1
         *****             Actor Information
    0010   16 Bitstring    1 LCPTLV         TLV_type Actor Information
              .... ...1      LCPACTOR       X'01' LCPACTOR Actor Information
    0011   17 Bitstring    1 LCPAILEN       Actor Information Length
              ...1 .1..      LCPAISIZ       X'14' LCPAISIZ Actor Information
                                            Length
    0012   18 Bitstring   15 LCPAINFO (0)   Entire LACP Actor Information
    0012   18 Signed       2 LCPASYSP       Actor System Priority
    0014   20 Bitstring    6 LCPASYS        Actor System ID
    001A   26 Signed       2 LCPAKEY        Actor Key
    001C   28 Signed       2 LCPAPPRI       Actor Port Priority
    001E   30 Signed       2 LCPAPORT       Actor Port
     Expired           : Indicates the Actor's Receive machine
                         state.
                            0 = Expired  (not valid)
                            1 = Valid
          Defaulted         : Flag indicates that the Actor's Receive
                              Machine is using defaulted operational
                              partner information.
          Distributing      : Datagram Distribution State
                                 0 = Distribution disabled
                                 1 = Distribution enabled
          Collecting        : Datagram Collecting State
                                 0 = No incomming datagrams accepted
                                 1 = Collecting incomming datagrams
          Synchronization   : Current link status
                                 0 = Out of SYNC (not in group)
                                 1 = In SYNC  (Allocated to the
                                     correct LinkAG group)
          Aggregation       : Indicates that the system considers
                              this link to be aggregatable.
                                 0 = Individual Link
                                 1 = Aggregatable
          LACP_Timeout      : Indicates the time-out control value
                              with regard to this link.
                                 0 = Long time-out
                                 1 = Short time-out
          LACP_Activity     : Indicates the Activity control value
                              with regard to this link.
                                 0 = Passive LACP
                                 1 = Active  LACP
    0020   32 Bitstring    1 LCPASTAT       Actor State
              1... ....      LCPEXP         X'80' LCPEXP Expired
              .1.. ....      LCPDEF         X'40' LCPDEF Defaulted
              ..1. ....      LCPDIST        X'20' LCPDIST Distributing
              ...1 ....      LCPCOL         X'10' LCPCOL Collecting
              .... 1...      LCPSYNC        X'08' LCPSYNC Synchronization
              .... .1..      LCPAGG         X'04' LCPAGG Aggregation
              .... ..1.      LCPTIMEO       X'02' LCPTIMEO LACP_Timeout
              .... ...1      LCPCCTVY       X'01' LCPCCTVY LACP_Activity
              ...1 11..      LCPENABL       LCPCOL+LCPAGG+LCPSYNC LCPENABL
                                            Port enabled in group
    0021   33 Bitstring    3 *              Reserved for Future Use
         *****             Partner Information
    0024   36 Bitstring    1 LCPPTYP        TLV_type Partner Information
              .... ..1.      LCPTYPE        X'02' LCPTYPE Partner Information
    0025   37 Bitstring    1 LCPPILEN       Partner Information Length
              ...1 .1..      LCPPISIZ       X'14' LCPPISIZ Partner
                                            Information Length
    0026   38 Bitstring   15 LCPART (0)     Entire LACP Partner Information
    0026   38 Bitstring    8 LCPSYSID (0)   Partner System INFO
    0026   38 Signed       2 LCPSYSP        Partner System Priority
    0028   40 Bitstring    6 LCPSYS         Partner System ID
    002E   46 Signed       2 LCPKEY         Partner Key
    0030   48 Bitstring    4 LCPPRTID (0)   Partner Port Information
    0030   48 Signed       2 LCPPORTP       Partner Port Priority
    0032   50 Signed       2 LCPORT         Partner Port
    0034   52 Bitstring    1 LCPSTATE       Partner State
    0035   53 Bitstring    3 *              Reserved for Future Use
         *****           Collector Information
    0038   56 Bitstring    1 LCPCTVL        TLV_type Collector Information
              .... ..11      LCPCINFO       X'03' LCPCINFO Collector
                                            Information
    0039   57 Bitstring    1 LCPCILEN       Collector Information Length
              ...1 ....      LCPCISIZ       X'10' LCPCISIZ Collector
                                            Information Length
    003A   58 Signed       2 LCPDELAY       Collector Maximum Delay
    003C   60 Signed       4 * (3)          Reserved for Future Use
    0048   72 Bitstring    1 LCPTTVL        TLV_type Terminator
              .... ....      LCPTINFO       X'00' LCPTINFO Terminator Length
    0049   73 Bitstring    1 LCPCTLEN       Terminator Length
              .... ....      LCPTLVEN       X'00' LCPTLVEN Terminator Size
    004A   74 Bitstring   50 *              Reserved for Future Use
              0000007C       LCPMSIZE       *-LCPDU Minimum size of a LACP
                                            PDU Frame Check Sequence will be
                                            added/removed by OSA LCPFCS DS F
                                            Frame Check Sequence
    007C  124 Bitstring    1 LCP$END (0)    The end
          Notes      : The following assembler equates are defined and can be
                used but do not appear in the control block expansion
                because they are in the PLX section and PRINT OFF,
                NOGEN are in effect.

LCPDU Storage Layout | Top of page

    *** LCPDU - LinkAG LACP Protocol-Data-Unit (PDU) c/b
    *
    *     +-----------------------------------------+-------------+
    *   0 |                LCPDEST                  |   (006)-    |
    *     +---------------------------+-------------+------+------+
    *   8 |        -LCPSOURC          |   LCPLEN    |:STYPE|LCPVER|
    *     +------+------+-------------+-------------+------+------+
    *  10 |LCPTLV|:AILEN|  LCPASYSP   |         LCPASYS-          |
    *     +------+------+-------------+-------------+-------------+
    *  18 |   -(014)    |  LCPAKEY    |  LCPAPPRI   |  LCPAPORT   |
    *     +------+------+-------------+------+------+-------------+
    *  20 |:ASTAT|////////////////////|:PTYP |:PILEN|  LCPSYSP    |
    *     +------+--------------------+------+------+-------------+
    *  28 |                 LCPSYS                  |   LCPKEY    |
    *     +-------------+-------------+------+------+-------------+
    *  30 |  LCPPORTP   |   LCPORT    |:STATE|////////////////////|
    *     +------+------+-------------+------+--------------------+
    *  38 |:CTVL |:CILEN|  LCPDELAY   |///////////////////////////|
    *     +------+------+-------------+///////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     +------+------+-----------------------------------------+
    *  48 |:TTVL |:CTLEN|/////////////////////////////////////////|
    *     +------+------+/////////////////////////////////////////|
    *  50 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////+---------------------------+
    *     |///////////////////////////|
    *     +---------------------------+
    *
    *** LCPDU - LinkAG LACP Protocol-Data-Unit (PDU) c/b

LCPDU Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    LCP$END        007C
    LCPACTOR       0010 01
    LCPAGG         0020 04
    LCPAILEN       0011
    LCPAINFO       0012
    LCPAISIZ       0011 14
    LCPAKEY        001A
    LCPAPORT       001E
    LCPAPPRI       001C
    LCPART         0026
    LCPASTAT       0020
    LCPASYS        0014
    LCPASYSP       0012
    LCPCCTVY       0020 01
    LCPCILEN       0039
    LCPCINFO       0038 03
    LCPCISIZ       0039 10
    LCPCOL         0020 10
    LCPCTLEN       0049
    LCPCTVL        0038
    LCPDEF         0020 40
    LCPDELAY       003A
    LCPDEST        0000
    LCPDIST        0020 20
    LCPENABL       0020 1C
    LCPEXP         0020 80
    LCPKEY         002E
    LCPLACP        000E 01
    LCPLEN         000C
    LCPMSIZE       004A 0000007C
    LCPORT         0032
    LCPPILEN       0025
    LCPPISIZ       0025 14
    LCPPORTP       0030
    LCPPRTID       0030
    LCPPTYP        0024
    LCPSOURC       0006
    LCPSPLAH       0000 0LCPDEST
    LCPSPLAL       0000 02
    LCPSPTF        000C 00LCPLEN
    LCPSTATE       0034
    LCPSTYPE       000E
    LCPSYNC        0020 08
    LCPSYS         0028
    LCPSYSID       0026
    LCPSYSP        0026
    LCPTIMEO       0020 02
    LCPTINFO       0048 00
    LCPTLV         0010
    LCPTLVEN       0049 00
    LCPTTVL        0048
    LCPTYPE        0024 02
    LCPVER         000F
    LCPVER1        000F 01
    LCPVID         000C

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:28:50 EDT.
Copyright IBM Corporation, 1990, 2020