This course provides a thorough and comprehensive introduction into recovery and restart procedures for both the Db2 for z/OS system and its data. The course describes and explains in detail the components, utilities and procedures involved in data and system backup and recovery, together with the various methods of utilising them to ensure maximum availability.
This course is applicable to all Db2 for z/OS environments, up to and including Db2 11 for z/OS.
A good knowledge of TSO/ISPF, SQL and general Db2 principles, structure and components.
Delegates will learn how to
- list all of the major system, backup and recovery components
- describe the need for Db2 logging to assist in recovery situations
- describe the need for and use of all Db2 utilities
- use the Db2 utilities and service aids specific to problem determination and recovery situations
- identify when service aids may be required for use in recovery situations
- describe the additional considerations when backing up and recovering catalog and directory tablespaces
- describe the actions taken during normal start-up, operation, and shut-down of the Db2 system
- describe the additional actions necessary following an abnormal termination of the Db2 system
- explain why and how a deferred restart may be performed and understand the effect it will have on the Db2 system and data
- explain why and how a conditional restart may be performed and the effect it will have on the Db2 system and data
- understand the options available for a conditional restart and when each may be required
- analyse any outstanding work following a deferred or conditional restart, and take the actions required to complete it
- describe the structure and format of Db2 pagesets
- analyse and repair broken Db2 pages
- interpret common error messages, and decide upon the actions required
- understand and implement Db2 system and data recovery and restart procedures.
Db2 architecture overview; working storage areas; storage pools; buffer pools; Db2 attachments; logging & recovery datasets; system databases; Db2 data objects; object characteristics; SQL overview; Db2 Interactive (Db2i).
Db2 logging; active and archive logs; boot-strap data set (BSDS); unit of recovery; two phase commit protocol; logging parameters; size & number of logs; checkpoints; checkpoint records; controlling logging using commands.
Introduction to Db2 Utilities
Online and stand-alone Db2 utilities; invoking online utilities using Db2i; utility control statements; using LISTDEF & TEMPLATE; use of wild Cards with LISTDEF; TEMPLATE options.
Utilities for Backup & Recovery
Backup & recovery components; use of SYSIBM.SYSCOPY; use of SYSIBM.SYSLGRNX; the COPY utility; using LISTDEF and TEMPLATE; COPYTOCOPY utility; MERGECOPY utility; QUIESCE utility; RECOVER utility; RECOVER using LISTDEF; recovery involving referential integrity, large object (LOB) and XML data: identifying consistent recovery points; point in time recovery; p-i-t recovery implications for RI, LOB and XML data; resetting status codes; REBUILD INDEX utility; REPORT utility; MODIFY utility; BACKUP SYSTEM utility; RESTORE SYSTEM utility; Restoring to a specified point; RECOVER using system-level backups.
Utilities for Data Integrity
CHECK DATA utility; CHECK DATA - SCOPE; CHECK DATA - SHRLEVEL; CHECK INDEX utility; CHECK LOB utility; REPAIR utility.
Other Online Utilities
LOAD utility; REORG TABLESPACE utility; Using shadow copies during REORG; Removal of BUILD2 phase; Shadow copies - FASTSWITCH; RUNSTATS utility; STOSPACE utility; UNLOAD utility.
Stand-Alone Utilities (service aids)
Invoking stand-alone utilities; DSN1COPY utility; DSN1PRNT utility; DSNJU004 (print log map) utility; DSNJU003 (change log inventory) utility; DSN1LOGP utility; DSN1CHKR utility; DSN1COMP utility; DSNJLOGF utility; DSNJCNVB utility.
Catalog & Directory Recovery
Catalog / Directory recovery implications; recovery sequence; Catalog & Directory point-in-time recovery; recovery implications; system-wide points of consistency.
Db2 System and Operations
Db2 commands; Starting Db2; Phase 1: log initialisation; Phase 2: current status rebuild; Phase 3: forward log recovery; Phase 4: backward log recovery; Start-up messages; Processing log records; Controlling Lock Manager (IRLM); Controlling Distributed Data Facility; Controlling CICS attachment; Other CICS Attachment commands; Controlling IMS Attachment; Other IMS Attachment commands; Controlling Threads; Controlling databases; Controlling buffer pools; Other Db2 commands; Stopping Db2.
Abnormal Termination & Restart
Db2 error messages & reason codes; data integrity considerations; log initialisation/current status rebuild/forward & backward log recovery implications; in-doubt threads and resolution; processing redo/undo records; deferred restart and its implications; delaying backout of long running tasks; conditional restart; creating a conditional restart control record, log truncation, limit restart, bypass backout, cold start, conditional restart implications; DSN1LOGP; cleaning up.
Db2 Physical Data Storage
VSAM file requirements; creating VSAM files; page sets; page set structure; index structure; index keys & pointers; data navigation; RIDS, pointers, and holes; table row header format; large object (LOB) data; large object columns; XML data; XML storage structure names; page set status; page set restrictions; analysing and fixing broken pages.
Problem Analysis and Handling
Basic code structure; Db2 messages and codes; Db2 subcomponents; Db2 control blocks; problem identification and resolution; basic dump analysis; identifying SQL statement; diagnosis traces and utilities; potential problem areas; active log out of space; active log I/O errors; archive log I/O errors; BSDS errors; forced single BSDS mode; recovering BSDS; data errors; down level datasets.