Distributed transaction resources | IBM SC34-7012-01 instruction

vDifferent TCT from last run. CICS installs the TCT only, and does not apply the warm keypoint information, effectively making this a cold start for these devices.

Note: CICS TS for z/OS, Version 4.1 supports only remote TCAM terminals—that is, the only TCAM terminals you can define are those attached to a remote, pre-CICS TS 3.1, terminal-owning region by TCAM/DCB.

Distributed transaction resources

CICS retrieves its logname from the recovery manager control record in the global catalog for use in the “exchange lognames” process with remote systems. Resynchronization of indoubt units of work takes place after CICS completes reconnection to remote systems.

See the CICS Recovery and Restart Guide for information about recovery of distributed units of work.

URIMAP definitions and virtual hosts

Installed URIMAP definitions for CICS Web support are restored from the global catalog, including their enable status. Virtual hosts, which are created by CICS using the host names specified in installed URIMAP definitions, are also restored to their former enabled or disabled state.

Chapter 5. CICS warm restart 59

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IBM SC34-7012-01 manual Distributed transaction resources, Urimap definitions and virtual hosts

Contents

Recovery and Restart Guide Page Recovery and Restart Guide Copyright IBM Corporation 1982 Contents Restart Part 3. Implementing recovery Programming for recovery 141 Part 4. Appendixes 241 Disaster recovery 223 Who should read this book How to use this bookPreface What this book is about Viii Cics TS for z/OS 4.1 Recovery and Restart Guide Copyright IBM Corp Cics TS for z/OS 4.1 Recovery and Restart Guide Part 1. Cics recovery and restart concepts Cics TS for z/OS 4.1 Recovery and Restart Guide Logging changes Recovery and restart facilitiesMaintaining the integrity of data Role of Cics Minimizing the effect of failures Cics backward recovery backout Recoverable resources Emergency restart backout Dynamic transaction backout Forward recovery of Cics data sets Cics forward recovery Forward recovery for non-VSAM resources Failures that require Cics recovery processingCics recovery processing following a communication failure XCF/MRO partner failures Cics recovery processing following a system failure Cics recovery processing following a transaction failure Recovery and restart facilities Cics TS for z/OS 4.1 Recovery and Restart Guide Shunted units of work Resource recovery in CicsUnits of work Active and retained states for locks Locks Synchronization points Units of work and syncpoints Examples of synchronization points Backout of units of work Cics recovery manager DB2 Coordinating updates to local resources Managing indoubt units of work Coordinating updates in distributed units of work Information recorded on the system log Resynchronization after system or connection failureCics system log User journals and automatic journaling Forward recovery logsSystem activity keypoints Resource recovery in Cics Cics TS for z/OS 4.1 Recovery and Restart Guide First quiesce stage Shutdown and restart recoveryNormal shutdown processing Third quiesce stage Second quiesce stage Shunted units of work at shutdown Warm keypoints Perform Immediate not recommended Flushing journal buffersImmediate shutdown processing Perform Shutdown Immediate Dfhcesd Shutdown requested by the operating system Shutdown assist transaction Uncontrolled termination Global catalog Cataloging Cics resources Local catalog Shutdown initiated by Cics log manager Effect of problems with the system log DFHRM0403 and DFHRM0404 How the state of the Cics region is reconstructed About this task Overriding the type of start indicatorWarm restart Emergency restart An initial start of Cics Recovery of data during an emergency restartCold start Dynamic RLS restart MNPS, multinode persistent sessions Recovery with Vtam persistent sessionsRunning with persistent sessions support SNPS, single-node persistent sessions Situations in which sessions are not reestablished Situations in which Vtam does not retain sessions Running without persistent sessions support Regions that do have persistent sessions support Cics TS for z/OS 4.1 Recovery and Restart Guide Part 2. Recovery and restart processes Cics TS for z/OS 4.1 Recovery and Restart Guide Starting Cics with the START=COLD parameter Cics cold start Vsam Files Data tables Temporary storageTransient data Temporary storage data sharing server Library resources Resource definitions dynamically installedTransactions Journal names and journal models Terminal control resources Committing and cataloging resources installed from the CSDMonitoring and statistics Starting Cics with the START=INITIAL parameter Installable set installDistributed transaction resources Dump table Cics cold start Cics TS for z/OS 4.1 Recovery and Restart Guide Rebuilding the Cics state after a normal shutdown Cics warm restart Recreating non-RLS retained locks Reconnecting to Smsvsam for RLS accessData set name blocks Trigger levels for Terminal and System only TDINTRA=NOEMPTY the default No autoinstall for programs Start requests Autoinstall for programs Tcam and sequential Bsam devices CSD-defined resource definitions Urimap definitions and virtual hosts Cics TS for z/OS 4.1 Recovery and Restart Guide Driving backout processing for in-flight units of work Recovering after a Cics failureRecovering information from the system log Cics emergency restart Rebuilding the Cics state after an abnormal termination Effect of delayed recovery on Pltpi processingOther backout processing Recreating non-RLS retained locks Reconnecting to Smsvsam for RLS accessRLS restart processing and orphan locks Start requests Distributed transaction resources Cics TS for z/OS 4.1 Recovery and Restart Guide Restrictions Automatic restart managementCics ARM processing Before you begin Registering with ARMWaiting for predecessor subsystems De-registering from ARM Cics restart JCL and parameters Failing to registerARM couple data sets Cics Start options Connecting to VtamWorkload policies Server ARM processing Covr transactionMessages associated with automatic restart Automatic restart of Cics data-sharing servers ARMELEMENTNAME=elementname Server commands for ARM supportWaiting on events during initialization Server initialization parameters for ARM support Commit-failed Unit of work recovery and abend processingUnit of work recovery In-flight-failed Indoubt-failed Transaction backoutBackout-failed Cics data tables FilesBdam files and Vsam Esds files Start requests Intrapartition transient dataAuxiliary temporary storage Restart of started transactions Start with recoverable data ProtectStart with nonrecoverable data no Protect Start with nonrecoverable data Protect Basic mapping support BMS messages Exec Cics Cancel requests Backout-failed recovery Disposition of data sets after backout failures ErrorTransient data Retrying backout-failed units of work Smsvsam server failure Open errorLogical delete not performed Coupling facility cache structure failure DFSMSdss non-BWO backup in progressDuplicate key error Smsvsam server recycle during backout None of the above Commit-failed recoveryLock structure full error Indoubt failure recovery Investigating an indoubt failure Cemt Inquire UOW details of UOW AC0CD65E5D990800 Cemt Inquire UOWENQ-details of a lock associated with a UOW Cache failure support Recovery from failures associated with the coupling facility Notifying Cics of Smsvsam restart Lost locks recoveryRebuilding the lock structure Performing lost locks recovery for failed units of work Connection failure to a coupling facility lock structure MVS system recovery and sysplex recoveryConnection failure to a coupling facility cache structure Exit code Transaction abend processing Transaction restart Abnormal termination of a task Processing operating system abends and program checks Actions taken at transaction failure Unit of work recovery and abend processing Cics TS for z/OS 4.1 Recovery and Restart Guide Terminal error program Dfhtep Communication error processingTerminal error processing Node error program Dfhznep Intersystem communication failures Part 3. Implementing recovery and restart Cics TS for z/OS 4.1 Recovery and Restart Guide Application design considerations Planning aspects of recoveryQuestions relating to recovery requirements Validate the recovery requirements statement Communications between application and user Designing the end user’s restart procedureEnd user’s standby procedures Security System definitions for recovery-related functionsSystem recovery table SRT Resource definitions for recovery Program list table PLT Documentation and test plansTransient data queues Temporary storage table Cics TS for z/OS 4.1 Recovery and Restart Guide Defining system and general log streams General log streams Defining log streams to MVSDefining system log streams System log streams With a Journalmodel definition Specifying a Journalmodel resource definitionWithout a Journalmodel definition Model log streams for Cics system logs Recovery considerations Sharing system logger structures between 2 MVS images About this task Activity keypointingVarying the model log stream name System log scan during restart Keeping system log data to a minimum Moving units of work to the secondary log Log-tail deletion Retrieving user records from the system log Writing user-recovery dataAvoiding retention periods on the system log Long-running transactions Defining forward recovery log streamsAbout this task Procedure What to do next Model log streams for Cics general logs Defining the log of logs Merging data on shared general log streams Reading log streams offline Log of logs failure Time stamping log and journal records Adjusting local timeEffect of daylight saving time changes Offline utility program, Dfhjup Cics TS for z/OS 4.1 Recovery and Restart Guide DTIMOUTNO1-6800 Defining recoverability for CICS-managed resourcesRecovery for transactions Defining transaction recovery attributes WAITTIME00,00,00dd,hh,mm Indoubt options for distributed transactions Sharing data sets with batch jobs Recovery for filesFile-owning regions and RLS access Vsam files Backward recovery Basic direct access method BdamDefining files as recoverable resources Forward recovery Recoveryall Vsam files accessed in non-RLS mode Inquiring on recovery attributes Vsam files accessed in RLS mode Overriding open failures at the Xfcnrec global user exit File recovery attribute consistency checking non-RLSBdam files CSD data set Cics responses to file open requests Backward recovery Implementing forward recovery with user-written utilitiesImplementing forward recovery with Cics Vsam Recovery Recovery for intrapartition transient data Physical recovery Logical recovery No recovery Forward recovery Input extrapartition data sets Recovery for extrapartition transient data Output extrapartition data sets Using post-initialization Pltpi programsRecovery for temporary storage Configuring Cics to support persistent messages Recovery for Web services Results What to do next Defining local queues in a service provider Persistent message processing Error processing Defining recoverability for CICS-managed resources Cics TS for z/OS 4.1 Recovery and Restart Guide Splitting the application into transactions Programming for recoveryDesigning applications for recovery Cics TS for z/OS 4.1 Recovery and Restart Guide Dividing transactions into units of work SAA-compatible applicationsProgram design Pseudoconversational processing Processing dialogs with usersConversational processing Main storage areas Cics recoverable resourcesMechanisms for passing data between transactions Designing to avoid transaction deadlocks Implications of interval control Start requests Terminal paging through BMS Using transient data queuesImplications of automatic task initiation TD trigger level Transaction failures Managing transaction and system failures Dynamic transaction backout Handle Abend commandsExec Cics Syncpoint Rollback command Transaction restart after DTB Use of the program error program DfhpepSystem failures Handling abends and program level abend exits Processing the Ioerr condition Command Information provided Locking enqueuing on resources in application programs Start Transid commandsPL/I programs and error handling Implicit locking for files Nonrecoverable files Recoverable files Cics TS for z/OS 4.1 Recovery and Restart Guide Writeq TD Readq TD Deleteq TD Implicit enqueuing on logically recoverable TD destinationsImplicit enqueuing on recoverable temporary storage queues Sequential methods HSAM, HISAM, Shisam Implicit enqueuing on DL/I databases with DbctlExplicit enqueuing by the application programmer Direct methods HDAM, Hidam Deadlock Possibility of transaction deadlock User exits for transaction backout Where you can add your own code Xfcbfail global user exit Xrcinit exitXrcinpt exit Coding transaction backout exits Xfcldel global user exitXfcbover global user exit Xfcbout global user exit CICS-supplied PEP Using a program error program PEP Your own PEP Omitting the PEP Cics TS for z/OS 4.1 Recovery and Restart Guide Quiescing RLS data sets Resolving retained locks on recoverable resources Illustration of the quiesce flow across two Cics regions RLS quiesce and unquiesce functions MVS1 MVS2 Cics AOR1 Cics AOR2 Other quiesce interface functions Non-BWO data set backup start Forward recovery complete Non-BWO data set backup endBWO backup start BWO backup end Quiesce coupling facility cache available Switching from RLS to non-RLS access modeLost locks recovery complete Exception for read-only operations What can prevent a switch to non-RLS access mode? Investigating which retained locks are held and why Inquire Dsname Resolving retained locks and preserving data integrity Shcds List subcommands Choosing data availability over data integrity Batch-enabling sample programs Cemt command examples Uowdsnfail Overriding retained locks Permitnonrlsupdate subcommandDenynonrlsupdate subcommand Special case lost locks Post-batch processing Coupling facility data table retained locks Using the Repro method Moving recoverable data sets that have retained locksProcedure for moving a data set with retained locks Shcds Frsetrr Using the Export and Import functions Rebuilding alternate indexes Forward recovery of data sets accessed in RLS mode Forward recovery procedures Recovery of data set with volume still available Alter the new data set name Recovery of data set with loss of volumeIssue the Frbind subcommand Issue the Frresetrr subcommand Volume recovery procedure using Cfvol Quiesce Forward recovery procedures Example of recovery using data set backup Shcds LISTSUBSYSDS’ADSWA01D’ Vary SMS,SMSVSAM,FORCEDELETELOCKSTRUCTURE Inquire Uowdsnfail Status Results Example of recovery using volume backup Above command produced the following message Catalog recovery Close all files Forward recovery of data sets accessed in non-RLS modeProcedure for failed RLS mode forward recovery operation Forward recovery procedures Uowactioncommit Backout Force Procedure for failed non-RLS mode forward recovery operation Cics TS for z/OS 4.1 Recovery and Restart Guide BWO and concurrent copy Backup-while-open BWOBWO and backups Component name Full DFSMS/MVS name Previous product Name BWO requirements Vsam control interval or control area split Hardware requirementsWhich data sets are eligible for BWO Results Specifying BWO using access method servicesHow you request BWO Specifying BWO on Cics file resource definitions Batch jobs Systems administrationRemoving BWO attributes BWO processing Back-level data sets First file opened in non-RLS mode against a clusterFile opening Subsequent files opened when use count is zero Subsequent files opened when use count is not zero Restriction for Vsam upgrade set File closing non-RLS mode Immediate or uncontrolled shutdown Data set backup and restoreShutdown and restart Controlled shutdown Invalid state changes for BWO attributes Vsam access method services Non-SMS managed storage Forward recovery loggingData set restore Data sets Recovery point non-RLS mode Recovering Vsam spheres with AIXs ASM XOPTSCICS,NOEPILOG,SP An assembler program that calls Dfsms callable services DS 8C MVC MVC SUCMSG18,SUCTXT1 SUCMSG21,SUCTXT2 Cics TS for z/OS 4.1 Recovery and Restart Guide Why have a disaster recovery plan? Disaster recovery Disaster recovery testing Tier 1 physical removal Six tiers of solutions for off-site recoveryTier 0 no off-site data Disaster recovery tier 1 physical removal Tier Tier 2 physical removal with hot siteTier 3 electronic vaulting Summarizes the tier 3 solution Tier 0-3 solutions Tier 0 Tier 4 active secondary site Disaster recovery tier 4 active secondary site Tier 6 minimal to zero data loss Tier 5 two-site, two-phase commit Summarizes the tier 6 solution Tier 4 Tier 4-6 solutions Peer-to-peer remote copy Pprc and extended remote copy XRC Disaster recovery and high availability Use Pprc for high value transactions Pprc or XRC? Other benefits of Pprc and XRC Remote Recovery Data Facility Disaster recovery personnel considerations Choosing between Rrdf and 3990-6 solutions Returning to your primary site Disaster recovery facilitiesMVS system logger recovery support Cics VR shadowing Cics Vsam Recovery Qsam copyRemote Recovery Data Facility support Remote site recovery for RLS-mode data sets Final summary 241 Part 4. Appendixes Cics TS for z/OS 4.1 Recovery and Restart Guide 243 Trademarks Cics books for Cics Transaction Server for z/OS Bibliography Other Cics publications Administration and ManagementCICSPlex SM books for Cics Transaction Server for z/OS Accessibility Cics TS for z/OS 4.1 Recovery and Restart Guide Index Airdelay DL/I 251 Tpend Readers’ Comments Wed Like to Hear from You Readers’ Comments Wed Like to Hear from You Page SC34-7012-01