LCPDU Back to Index page
 
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