Subchannel logout handler (SLH) record

The system writes a SLH record for any of the following channel-detected errors:
Table 1. Format of the SLH record
Offset Size (bytes) alignment (bits) Field name Description
Dec Hex
0 (0) 1 LRBHTYPE Class/Source:
    ..1. ..11   SLH Record; type=X'23'.
1 (1) 1 LRBHREL System/Release level:
    100. ....   OS/VS2.
    bits 3-7    
    0-1F   Release level 0-31.
2 (2) 1 LRBHSW0 Record-independent switches:
    1... ....   More records follow.
    0... ....   Last record.
    .1.. ....   Time-of-day (TOD) clock instruction issued.
    ..1. ....   Record truncated.
    ...1 ....   Record created by MVS/SP Version 2 or 3.
    .... 1...   TIME macro issued.
    .... .xxx   Reserved.
3 (3) 3   Record-dependent switches:
    Byte 0 LRBHSW1 Reserved.
    Byte 1 LRBHSW2 Reserved.
    Byte 2 LRBHSW3  
    bits 0-5   Reserved.
    bits 6-7   ‘01’ - Hard error - failure not recovered by the system. One or more jobs, or the operating system, may be lost or impacted. Hardware resources may be lost.
        ‘02’ - Degrade mode - failure was successfully recovered by the system. However, hardware resources may be lost, performance may be degraded, or a time-dependent application may be impacted.
        ‘03’ - Soft error - failure was successfully recovered by the system. A time-dependent application may be impacted.
6 (6) 1 LRBHCNT Record count:
    bits 0-3 LRBSEQ Record sequence number.
    bits 4-7 LRBNUM Total number of physical records in this logical record.
7 (7) 1   Reserved.
8 (8) 4 LRBHDATE System date of incident.
12 (C) 4 LRBHTIME System time of incident.
16 (10) 1 LRBHCPID Machine version code.
17 (11) 3 LRBHCSER Central processor serial number.
20 (14) 2 LRBHMDL Central processor machine model number.
22 (16) 2 LRBHMCEL Reserved.
         
        END OF STANDARD HEADER
24 (18) 8 SLHJOBNM Job name or user ID.
32 (20) 8 SLHCCW Last processed CCW.
40 (28) 4 SLHDEVT Device type.
44 (2C) 8 SLHERPIB ERP information block.
44 (2C) 1 SLHESW01 First byte of ESW.
45 (2D) 3 SLHRSVD1 Reserved.
48 (30) 1 SLHFLG1 Flag byte.
    0... .... SLHSSCH No status stored after SSCH.
    .1.. .... SLHINT Status stored after I/O interruption.
    ..0. .... SLHTSCH No status stored after TSCH.
    ...0 .... SLHHSCH No status stored after HSCH.
    .... x...   Reserved.
    .... .1.. SLHSENSE Sense data was stored.
    .... ..1. SLHCSWCT CSW count is valid.
    .... ...1 SLHRETRY If on, operation cannot be retried.
49 (31) 1 SLHLPUM Last path used mask.
50 (32) 1 SLHVALID Validity indicators.
    x... ....   Reserved.
    .1.. .... SLHVLPUM LPUM consistent with log indicators.
    ..1. .... SLHVTERM Abnormal end code validity.
    ...1 .... SLHVSEQC Sequence code validity.
    .... 1... SLHVDVST Device status validity.
    .... .1.. SLHVCCW CCW address validity.
    .... ..1. SLHVDVNO Device number validity.
    .... ...1 SLHVDVNU Device number validity.
51 (33) 1 SLHTRMSQ Ending and sequence codes:
    xx.. .... SLHTRMCD Ending code:
    00.. ....   Interface disconnect.
    01.. ....   Stop, stack or normal end.
    10.. ....   Selective reset.
    ..xx ....   Reserved.
    .... 1... SLHIOALT I/O error alert.
    .... .xxx SLHSEQCD Sequence code
    .... .000   Reserved.
    .... .001   Command sent but status not analyzed.
    .... .010   Command accepted by device but no data transferred.
    .... .011   At least one byte of data has been transferred.
    .... .100   Command not sent or sent but not yet accepted.
    .... .101   Command accepted but data transfer unpredictable.
    .... .110   Reserved.
    .... .111   Reserved.
52 (34) 64 SLHIRB IRB, which includes the SCSW (subchannel status word) and the ESW (extended status word). See z/OS® MVS™ Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the detailed format of the IRB.
116 (74) 4 SLHUCBAD UCB or RDEV address.
120 (78) 2 SLHDEVNO Device number.
122 (7A) 6 SLHVOLSR Volume serial number.
128 (80) 5 SLHUCBLV UCB level byte and mask.
133 (85) 2   Reserved.
135 (87) 1 SLHCHPID Channel path id.
136 (88) 4 SLHSID Subchannel ID number.
140 (8C) 4 SLHRSMAD Absolute address of storage or key error if available.
144 (90) 2 SLHRSMRC RSM return code for storage or key error.
146 (92) 2 SLHRSMER Error type.
    Byte 0   Reserved.
    Byte 1    
    xxxx xx..   Reserved.
    .... ..00   Other.
    .... ..01   Storage error.
    .... ..10   Key error.
148 (94) 4 SLHRSMST RSM status information.