Rebuilding damaged areas of a volume table using a volume data set

Patent metadata

Field	Value
Publication number	US-9785517-B2
Application number	US-201514735608-A
Country	US
Kind code	B2
Filing date	Jun 10, 2015
Priority date	Jun 10, 2015
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

Provided a computer program product, system, and method for rebuilding damaged areas of a volume table using a volume data set for managing data sets assigned data units in a volume in a storage. A determination is made of damaged areas in a volume table providing information on data sets allocated in the volume. The determined damaged areas are formatted to produce reformatted areas to make the volume table usable. A volume data set in the volume having information on data sets configured in the volume is processed to determine from the volume data set salvaged data sets comprising the data sets in the volume not indicated in the volume table. Data set information is rebuilt in the reformatted areas of the volume table for the salvaged data sets.

First claim

What is claimed is:

1. A computer program product for managing data sets assigned data units in a volume in a storage, wherein the computer program product comprises a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause operations, the operations comprising:
determining damaged areas in a volume table providing information on data sets allocated in the volume;
formatting the determined damaged areas to produce reformatted areas by writing empty data to the determined damaged areas to make the volume table usable;
processing a volume data set in the volume having information on data sets configured in the volume;
determining, from the volume data set salvaged data sets comprising the data sets in the volume not indicated in the volume table; and
rebuilding data set information in the reformatted areas of the volume table for the salvaged data sets.

2. The computer program product of claim 1 , wherein the operations further comprise:
indicating in a catalog stored external to the volume a location of the volume table and the volume data set.

3. The computer program product of claim 1 , wherein a first type of data set comprises records indexed by keys and a second type of data set comprises records grouped into blocks, wherein the volume data set includes a first type of volume record for the first type of data set having extents in the volume for a data set name, wherein the operations further comprise:
including, in a second type of volume, records for the second type of data set on extents in the volume assigned to data set names for the second type of data set.

4. The computer program product of claim 1 , wherein the operations further comprise:
determining, from the volume data set, extents assigned to the salvaged data sets, wherein the rebuilding the data set information comprises including the data set information determined from the volume data set in the reformatted areas.

5. The computer program product of claim 4 , wherein the volume data set has information on the data sets in the volume in a different format than data set records the volume table has on the data sets, wherein the operations further comprise:
converting the determined data set information on the data set from the volume data set to a format used in the data set records in the volume table, wherein the rebuilding the data set information comprises including the converted determined data set information in the data set records formatted in the reformatted areas.

6. The computer program product of claim 1 , wherein the volume table has data set records having information on data sets configured in the volume, wherein the formatting the determined damaged areas comprises:
formatting damaged tracks in the volume table to have fields of a data set record without information for a particular data set.

7. The computer program product of claim 1 , wherein the determining from the volume data set the data sets in the volume not indicated in the volume table comprises:
determining data sets in the volume by scanning the volume table;
determining data sets in the volume by scanning the volume data set for the volume; and
comparing the determined data sets from the volume table and the volume data set to determine the salvaged data sets indicated in the volume data set not indicated in the volume table.

8. The computer program product of claim 1 , wherein the operations further comprise:
returning a list of the salvaged data sets to a storage administrator indicating the data sets rebuilt in the volume table.

9. The computer program product of claim 1 , wherein the volume table comprises a volume table of contents, wherein the volume data set comprises a Virtual storage access method (VSAM) volume data set (VVDS), and wherein the VVDS includes VSAM volume records (VVRs) and non-VSAM volume records (NVRs) having information on data sets configured in the volume, wherein the VSRs and the NVRs in the VVDS are processed to determine the data sets configured in the volume.

10. A system for managing data sets assigned data units in a volume in a connected storage, comprising:
a processor; and
a computer readable storage medium including program code executed by the processor to perform operations, the operations comprising:
determining damaged areas in a volume table providing information on data sets allocated in the volume;
formatting the determined damaged areas to produce reformatted areas by writing empty data to the determined damaged areas to make the volume table usable;
processing a volume data set in the volume having information on data sets configured in the volume;
determining, from the volume data set, salvaged data sets comprising the data sets in the volume not indicated in the volume table; and
rebuilding data set information in the reformatted areas of the volume table for the salvaged data sets.

11. The system of claim 10 , wherein a first type of data set comprises records indexed by keys and a second type of data set comprises records grouped into blocks, wherein the volume data set includes a first type of volume record for the first type of data set having extents in the volume for data set names, wherein the operations further comprise:
including in a second type of volume records for the second type of data set information on extents in the volume assigned to data set names for the second type of data set.

12. The system of claim 10 , wherein the operations further comprise:
determining, from the volume data set extents assigned to the salvaged data sets, wherein the rebuilding the data set information comprises including the data set information determined from the volume data set in the reformatted areas.

13. The system of claim 10 , wherein the volume table has data set records having information on data sets configured in the volume, wherein the formatting the determined damaged areas comprises:
formatting damaged tracks in the volume table to have fields of a data set record without information for a particular data set.

14. The system of claim 10 , wherein the determining from the volume data set the data sets in the volume not indicated in the volume table comprises:
determining data sets in the volume by scanning the volume table;
determining data sets in the volume by scanning the volume data set for the volume; and
comparing the determined data sets from the volume table and the volume data set to determine the salvaged data sets indicated in the volume data set not indicated in the volume table.

15. The system of claim 10 , wherein the volume table comprises a volume table of contents, wherein the volume data set comprises a Virtual storage access method (VSAM) volume data set (VVDS), and wherein the VVDS includes VSAM volume records (VVRs) and non-VSAM volume records (NVRs) having information on data sets configured in the volume, wherein the VSRs and the NVRs in the VVDS are processed to determine the data sets configured in the volume.

16. A method for managing data sets assigned data units in a volume in a storage, comprising:
determining damaged areas in a volume table providing information on data sets allocated in the volume;
formatting the determined damaged areas by writing empty data to the determined damaged areas to produce reformatted areas to make the volume table usable;
processing a volume data set in the volume having information on data sets configured in the volume;
determining, from the volume data set, salvaged data sets comprising the data sets in the

Assignees

• IBM

Inventors

• Huber Harold S
• Malinowski Joseph V
• Reed David C
• Smith Max D

Classifications

• G06F11/1435

  using file system or storage system metadata · CPC title

• G06F3/0632

  by initialisation or re-initialisation of storage systems · CPC title

• G06F3/0673

  Single storage device · CPC title

• G06F11/1469 Primary

  Backup restoration techniques · CPC title

• G06F3/0661

  Format or protocol conversion arrangements · CPC title