How do I read IEHLIST and/or DSF PRINT VTOC outputs to identify DSCB issues reported by BMC AMI Storage Compaktor? |
Before answering that question, we must understand what is it that those utilities report. Every CKD DASD volume that is initialized and used on Mainframe systems contain their Volume Table Of Contents (VTOC). The VTOC keeps information of datasets that exist in that volume in Data Set Control Blocks (DSCB's). IEHLIST and DSF PRINT VTOC will list all the DSCBs from a VTOC. Here we are going to talk about 2 types of DSCB's: Format-1 DSCB and Format-3 DSCB. Each dataset has 1 corresponding Format-1 DSCB per volume. It is called Identifier and describes the first three extents and other information about a data set. The following link describes each field of the Format-1 DSCB and its meanings: https://www.ibm.com/docs/en/zos/2.1.0?topic=dscbs-how-found Below you will find an example of the same Format-1 DSCB reported by IEHLIST and FDR PRINT VTOC: IEHLIST
LINE 1 = DSNAME 0 . . . 4 . . . . 9 . . . .14 . . . .19 . . . .24 . . . .29 . . . .34 . . . .39 . . . .
LINE 2 = 44 . . . .49 . . . .54 . . . .59 . . . .64 . . . .69 . . . .74 . . . .79 . . . .84 . . . .89 . . . .94 . . . .
LINE 3 = 99 . . . 104 . . . 109 . . . 114 . . . 119 . . . 124 . . . 129 . . . 134 . . . 139 DSCB ADDR (CCHHR)
MVSRXL.SAMPLE.V10
F1C5E4F2C6F0C100017B003C0000006C0000C9C2D4D6E2E5E2F240404040407B003C84000000400090000C800050000000828000000904
B80A00000000010000030005001400010101001400020014000A01020014000B00150004000000010D 0000000107
DSF PRINT VTOC FDR522 COUNT FIELD 00000001072C0060 000000 D4E5E2D9 E7D34BE2 C1D4D7D3 C54BE5F1 F0404040 40404040 40404040 40404040 *MVSRXL.SAMPLE.V10 * 000020 40404040 40404040 40404040 * * 000000 F1C5E4F2 C6F0C100 017B003C 0000006C 0000C9C2 D4D6E2E5 E2F24040 4040407B *1EU2F0A...........IBMOSVS2 .* 000020 003C8400 00004000 90000C80 00500000 00828000 000904B8 0A000000 00010000 *...... .........................* 000040 03000500 14000101 01001400 02001400 0A010200 14000B00 15000400 0000010D *................................* The Format-3 DSCB is called the extension DSCB. It describes extents after the third extent of a non-VSAM data set or a VSAM data space. There is one Format-3 DSCB for each data set or VSAM data space on the volume that has more than three extents. There can be as many as 10 for a PDSE, HFS, extended format data set, or a VSAM data set cataloged in an integrated catalog facility catalog. The following link describes each field of the Format-3 DSCB and its meanings: https://www.ibm.com/docs/en/zos/2.1.0?topic=f3d-how-found Below you will find an example of the same Format-3 DSCB reported by IEHLIST and FDR PRINT VTOC: IEHLIST LINE 1 = DSNAME 0 . . . 4 . . . . 9 . . . .14 . . . .19 . . . .24 . . . .29 . . . .34 . . . .39 . . . . LINE 2 = 44 . . . .49 . . . .54 . . . .59 . . . .64 . . . .69 . . . .74 . . . .79 . . . .84 . . . .89 . . . .94 . . . . LINE 3 = 99 . . . 104 . . . 109 . . . 114 . . . 119 . . . 124 . . . 129 . . . 134 . . . 139 DSCB ADDR (CCHHR) FORMAT 3 DSCB 030303030103001500050015000D01040015000E00160007010500160008001700010106001700020017000A F301070017000B001800040108001800050018000D01090018000E00190007010A00190008001A0001010B001A0002001A000A010C001A 000B001B0004010D001B0005001B000D010E001B000E001C0007010F001C0008001D0001000000010E 000000010D FORMAT 3 DSCB 030303030110001D0002001D000A0111001D000B001E00040112001E0005001E000D0113001E000E001F0007 F30114001F0008002000010115002000020020000A01160020000B002100040117002100050021000D01180021000E0022000701190022 000800230001011A002300020023000A011B0023000B00240004011C002400050024000D000000010F 000000010E FORMAT 3 DSCB 03030303011D0024000E00250007011E0025000800260001011F002600020026000A01200026000B00270004 F30121002700050027000D01220027000E00280007012300280008002900010124002900020029000A01250029000B002A00040126002A 0005002A000D0127002A000E002B00070128002B0008002C00010129002C0002002C000A0000000110 000000010F FORMAT 3 DSCB 03030303012A002C000B002D0004012B002D0005002D000D012C002D000E002E0007012D002E0008002F0001 F3012E002F0002002F000A012F002F000B003000040130003000050030000D01310030000E003100070132003100080032000101330032 00020032000A01340032000B003300040135003300050033000D01360033000E003400070000000111 0000000110 FORMAT 3 DSCB 03030303013700340008003500010138003500020035000A01390035000B00360004013A003600050036000D F3013B0036000E00370007013C0037000800380001013D003800020038000A013E0038000B00390004013F003900050039000D01400039 000E003A00070141003A0008003B00010142003B0002003B000A0143003B000B003C00040000000112 0000000111 FORMAT 3 DSCB 030303030144003C0005003C000D0145003C000E003D00070146003D0008003E00010147003E0002003E000A F30148003E000B003F00040149003F0005003F000D014A003F000E00400007014B0040000800410001014C004100020041000A014D0041 000B00420004014E004200050042000D014F0042000E00430007015000430008004400010000000113 0000000112 FORMAT 3 DSCB 030303030151004400020044000A01520044000B004500040153004500050045000D01540045000E00460007 F3015500460008004700010156004700020047000A01570047000B004800040158004800050048000D01590048000E00490007015A0049 0008004A0001015B004A0002004A000A015C004A000B004B0004015D004B0005004B000D0000000114 0000000113 FORMAT 3 DSCB 03030303015E004B000E004C0007015F004C0008004D00010160004D0002004D000A0161004D000B004E0004 F30162004E0005004E000D0163004E000E004F00070164004F0008005000010165005000020050000A01660050000B0051000401670051 00050051000D01680051000E0052000701690052000800530001016A005300020053000A0000000115 0000000114 FORMAT 3 DSCB 03030303016B0053000B00540004000000000000000000000000000000000000000000000000000000000000 F3000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 0000000000000000000000000000000000000000000000000000000000000000000000000000000000 0000000115 DSF PRINT VTOC FDR522 COUNT FIELD 000000010D2C0060 000000 03030303 01030015 00050015 000D0104 0015000E 00160007 01050016 00080017 *................................* 000020 00010106 00170002 0017000A *............ * 000000 F3010700 17000B00 18000401 08001800 05001800 0D010900 18000E00 19000701 *3...............................* 000020 0A001900 08001A00 01010B00 1A000200 1A000A01 0C001A00 0B001B00 04010D00 *................................* 000040 1B000500 1B000D01 0E001B00 0E001C00 07010F00 1C000800 1D000100 0000010E *................................* FDR522 COUNT FIELD 000000010E2C0060 000000 03030303 0110001D 0002001D 000A0111 001D000B 001E0004 0112001E 0005001E *................................* 000020 000D0113 001E000E 001F0007 *............ * 000000 F3011400 1F000800 20000101 15002000 02002000 0A011600 20000B00 21000401 *3...............................* 000020 17002100 05002100 0D011800 21000E00 22000701 19002200 08002300 01011A00 *................................* 000040 23000200 23000A01 1B002300 0B002400 04011C00 24000500 24000D00 0000010F *................................* FDR522 COUNT FIELD 000000010F2C0060 000000 03030303 011D0024 000E0025 0007011E 00250008 00260001 011F0026 00020026 *................................* 000020 000A0120 0026000B 00270004 *............ * 000000 F3012100 27000500 27000D01 22002700 0E002800 07012300 28000800 29000101 *3...............................* 000020 24002900 02002900 0A012500 29000B00 2A000401 26002A00 05002A00 0D012700 *................................* 000040 2A000E00 2B000701 28002B00 08002C00 01012900 2C000200 2C000A00 00000110 *................................* FDR522 COUNT FIELD 00000001102C0060 000000 03030303 012A002C 000B002D 0004012B 002D0005 002D000D 012C002D 000E002E *................................* 000020 0007012D 002E0008 002F0001 *............ * FDR400 FDR DISK PRINT UTILITY PROGRAM - FDRTRKPR VER 5.4/90P - INNOVATION DATA PROCESSING DATE- 2024.011 PAGE- 0004 000000 F3012E00 2F000200 2F000A01 2F002F00 0B003000 04013000 30000500 30000D01 *3...............................* 000020 31003000 0E003100 07013200 31000800 32000101 33003200 02003200 0A013400 *................................* 000040 32000B00 33000401 35003300 05003300 0D013600 33000E00 34000700 00000111 *................................* FDR522 COUNT FIELD 00000001112C0060 000000 03030303 01370034 00080035 00010138 00350002 0035000A 01390035 000B0036 *................................* 000020 0004013A 00360005 0036000D *............ * 000000 F3013B00 36000E00 37000701 3C003700 08003800 01013D00 38000200 38000A01 *3...............................* 000020 3E003800 0B003900 04013F00 39000500 39000D01 40003900 0E003A00 07014100 *.................... ...........* 000040 3A000800 3B000101 42003B00 02003B00 0A014300 3B000B00 3C000400 00000112 *................................* FDR522 COUNT FIELD 00000001122C0060 000000 03030303 0144003C 0005003C 000D0145 003C000E 003D0007 0146003D 0008003E *................................* 000020 00010147 003E0002 003E000A *............ * 000000 F3014800 3E000B00 3F000401 49003F00 05003F00 0D014A00 3F000E00 40000701 *3........................... ...* 000020 4B004000 08004100 01014C00 41000200 41000A01 4D004100 0B004200 04014E00 *.. .............................* 000040 42000500 42000D01 4F004200 0E004300 07015000 43000800 44000100 00000113 *................................* FDR522 COUNT FIELD 00000001132C0060 000000 03030303 01510044 00020044 000A0152 0044000B 00450004 01530045 00050045 *................................* 000020 000D0154 0045000E 00460007 *............ * 000000 F3015500 46000800 47000101 56004700 02004700 0A015700 47000B00 48000401 *3...............................* 000020 58004800 05004800 0D015900 48000E00 49000701 5A004900 08004A00 01015B00 *................................* 000040 4A000200 4A000A01 5C004A00 0B004B00 04015D00 4B000500 4B000D00 00000114 *................................* FDR522 COUNT FIELD 00000001142C0060 000000 03030303 015E004B 000E004C 0007015F 004C0008 004D0001 0160004D 0002004D *................................* 000020 000A0161 004D000B 004E0004 *............ * 000000 F3016200 4E000500 4E000D01 63004E00 0E004F00 07016400 4F000800 50000101 *3...............................* 000020 65005000 02005000 0A016600 50000B00 51000401 67005100 05005100 0D016800 *................................* 000040 51000E00 52000701 69005200 08005300 01016A00 53000200 53000A00 00000115 *................................* FDR522 COUNT FIELD 00000001152C0060 000000 03030303 016B0053 000B0054 00040000 00000000 00000000 00000000 00000000 *................................* 000020 00000000 00000000 00000000 *............ * 000000 F3000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 *3...............................* 000020 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 *................................* LINE 000040 SAME AS ABOVE So, based on the example provided, reading the Format-1 DSCB for dataset MVSRXL.SAMPLE.V10 here is some important information that we can extract: - Format-1 DSCB location is 0000000107; - The first or only volume containing the data set/space is EU2F0A; - Volume sequence number is 1; - Dataset was created on 2023.060 and has no expiration date; - There are 108 extents on that volume; - The first extent(00) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0003-05:0014-01; - The second extent(01) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0014-02:0014-10; - The third extent(02) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0014-11:0015:04; - The next extents will be described in Format-3 DSCB located at location 00000010D; Looking at the first Format-3 DSCB for that dataset at position 000000010D, this is what we can extract: - The fourth extent(03) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0015-05:0015:13; - The fifth extent(04) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0015-14:0016:07; ... - The sixteenth extent(15) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0028-08:0029:01; - The next extents will be described in Format-3 DSCB located at location 00000010E; And this repeats until you find the last Format-3 DSCB for that dataset located at 0000000115 where the last extent (107) is a user's data block extent or a prime area extent and is positioned at (CC-HH): 0083-11:0084:04. |