ID: Q161492
The information in this article applies to:
SNA Server 2.11 and later versions support the VTAM V4 feature referred to as "Dynamically Defined Dependent LUs" (DDDLU). The host support of DDDLU is indicated in the ACTPU sent to SNA Server. Upon receiving a request for a 3270 session, SNA Server will request that the host activate a LU for this session. The Host PU definition defines support for DDDLU by the use of the LUGROUP and LUSEED parameters, there will be no LUs defined in the PU definition. The SNA Server configuration, though, must have the LUs defined, although they will be displayed as inactive until a client requests a session.
NOTE: For information about DDDLU support in VTAM, please refer to the
following reference:
VTAM Network Implementation Guide, V4R1 for MVS/ESA, IBM document
number SC31-6419-00
For information about the format of these messages, please refer to
the following document:
IBM SNA Formats Guide, IBM document number GA27-3136-14
The Host indicates support of DDDLU in the PU Capabilities (x'80') ACTPU Control Vector by setting the first bit of the third byte of to 1.
DLC ---------------------------------------------- 15:57:44.82
DLC 04160000->01020201 DLC DATA
DLC DAF:00 OAF:00 ODAI:off Exp.
DLC ACTPU RQD SC FI BC EC DR1
DLC
DLC ---- Header at address 012D4828, 1 elements ----
DLC 00434F4D 4E4F2D00 000000FA 0100F200 <.COMNO-.......2.>
DLC
DLC ---- Element at address 017CE59C, start 10, end 24 ----
DLC 6B800011 12010500 00000001 800180 <k.............. >
^^^^^^ PU
Capabilities Control Vector
Byte 0 Vector Key = x'80'
Byte 1 Vector length
Byte 2 bit 0 Unsolicited NMVT support:
0 Sending node does not support unsolicited NMVTs for PSID.
1 Sending node does support unsolicited NMVTs for PSID.
Bit 1-7 Reserved
When using DDDLU, SNA Server will only receive an ACTPU from the Host. No
ACTLUs will flow until a session is requested (unless the PU definition has
static LUs defined in addition to the dynamic). When SNA Server receives
an OpenSSCP request for a 3270 display session, it will send a NMVT request
to the Host. This NMVT request will cause an ACTLU to be sent to the SNA
Server, allowing it to satisfy the request for a session.
DLC 01020201->04160000 DLC DATA
DLC DAF:00 OAF:00 ODAI:off Normal
DLC NMVT RQD FMD FI BC EC DR1
DLC
DLC ---- Header at address 012D4758, 1 elements ----
DLC 0102000C 10112C00 00000000 0100DE00 <......,.........>
DLC
DLC ---- Element at address 017CE59C, start 10, end 83 ----
DLC 0B800041 038D0000 00001000 3F00900A <...A........?...>
DLC 04010000 00000000 070D8205 10F0F0F0 <..........b..000>
DLC 03200103 30021910 00161109 130012F0 <. ..0..........0>
DLC F0F0F0F0 F0F2F0F0 F0F0F0F0 F0F0F00B <000002000000000.>
DLC 01091060 0C0A1000 1928 <...`.....( >
NMVT Request
0B8000 RH
41038D Header
0000 Retired
0000 PRID
10 0 unsolicited NMVT
00 only NMVT for this PRID
1 MS major vector contains SNA address list
0000 resrv
========MS Major vector=======
003F length
0090 Reply Product set ID <<<
______________________________
0A length
04 SNA Address List <<<
0100000000000007 local address= LU# we want an ACTLU for
______________________________
0D length
82 Port-Attached Device Config Description <<<
------------------------------
05 length
10 Port Number <<<
F0F0F0 number of the port
------------------------------
03 length
20 Power On Status <<<
01 device is currently powered on
------------------------------
03 length
30 Power-on Since Last Solicitation <<<
02 device was not powered on
______________________________
19 length
10 Product Set ID <<<
00 retired
------------------------------
16 length
11 Product ID <<<
09 0000 resv
1001 non-ibm hardware
------------------------------
13 length
00 Hardware Product ID <<<
12 product instance is identified by serial number
F0F0F0F0 machine type
F0F0F2 machine model number
F0F0 plant of manufacture
F0F0F0F0F0F0F0 sequence number
------------------------------
0B length
01 Emulator Product ID <<<
0910600C machine type of product being emulated
0A10001928 Model number product being emulated
<<< denotes vector
For more details on NMVT requests & Major vectors, please refer to the IBM SNA Formats Guide. The documentation of the PU Capabilities Control Vector was added to the Fifteenth Edition of the SNA Formats Guide (GA27-3136-14).
Additional query words: LU2 node ddlu
Keywords : prodsna sna3270
Version : 2.0 2.1 2.11 3.0
Platform : WINDOWS
Last Reviewed: November 8, 1997