RDF System Management Manual
Table Of Contents
- RDF System Management Manual
- What’s New in This Manual
- About This Manual
- 1 Introducing RDF
- RDF Subsystem Overview
- RDF Processes
- RDF Operations
- Reciprocal and Chain Replication
- Available Types of Replication to Multiple Backup Systems
- Triple Contingency
- Loopback Configuration (Single System)
- Online Product Initialization
- Online Database Synchronization
- Online Dumps
- Subvolume- and File-Level Replication
- Shared Access DDL Operations
- EMS Support
- SMF Support
- RTD Warning Thresholds
- Process-Lockstep Operation
- Support for Network Transactions
- RDF and NonStop SQL/MX
- Zero Lost Transactions (ZLT)
- Monitoring RDF Entities With ASAP
- 2 Preparing the RDF Environment
- 3 Installing and Configuring RDF
- 4 Operating and Monitoring RDF
- 5 Managing RDF
- Recovering From File System Errors
- Handling Disk Space Problems
- Responding to Operational Failures
- Stopping RDF
- Restarting RDF
- Carrying Out a Planned Switchover
- Takeover Operations
- Reading the Backup Database
- Access to Backup Databases in a Consistent State
- RDF and NonStop SQL/MP DDL Operations
- RDF and NonStop SQL/MX Operations
- Backing Up Image Trail Files
- Making Online Dumps With Updaters Running
- Doing FUP RELOAD Operations With Updaters Running
- Exception File Optimization
- Switching Disks on Updater UPDATEVOLUMES
- 6 Maintaining the Databases
- 7 Online Database Synchronization
- 8 Entering RDFCOM Commands
- 9 Entering RDFSCAN Commands
- 10 Triple Contingency
- 11 Subvolume- and File-Level Replication
- 12 Auxiliary Audit Trails
- 13 Network Transactions
- Configuration Changes
- RDF Network Control Files
- Normal RDF Processing Within a Network Environment
- RDF Takeovers Within a Network Environment
- Takeover Phase 1 – Local Undo
- Takeover Phase 2 – File Undo
- Takeover Phase 3 – Network Undo
- Takeover Phase 3 Performance
- Communication Failures During Phase 3 Takeover Processing
- Takeover Delays and Purger Restarts
- Takeover Restartability
- Takeover and File Recovery
- The Effects of Undoing Network Transactions
- Takeover and the RETAINCOUNT Value
- Network Configurations and Shared Access NonStop SQL/MP DDL Operations
- Network Validation and Considerations
- RDF Re-Initialization in a Network Environment
- RDF Networks and ABORT or STOP RDF Operations
- RDF Networks and Stop-Update-to-Time Operations
- Sample Configurations
- RDFCOM STATUS Display
- 14 Process-Lockstep Operation
- Starting a Lockstep Operation
- The DoLockstep Procedure
- The Lockstep Transaction
- RDF Lockstep File
- Multiple Concurrent Lockstep Operations
- The Lockstep Gateway Process
- Disabling Lockstep
- Reenabling Lockstep
- Lockstep Performance Ramifications
- Lockstep and Auxiliary Audit Trails
- Lockstep and Network Transactions
- Lockstep Operation Event Messages
- 15 NonStop SQL/MX and RDF
- Including and Excluding SQL/MX Objects
- Obtaining ANSI Object Names From Updater Event Messages
- Creating NonStop SQL/MX Primary and Backup Databases from Scratch
- Creating a NonStop SQL/MX Backup Database From an Existing Primary Database
- Online Database Synchronization With NonStop SQL/MX Objects
- Offline Synchronization for a Single Partition
- Online Synchronization for a Single Partition
- Correcting Incorrect NonStop SQL/MX Name Mapping
- Consideration for Creating Backup Tables
- Restoring to a Specific Location
- Comparing NonStop SQL/MX Tables
- 16 Zero Lost Transactions (ZLT)
- A RDF Command Summary
- B Additional Reference Information
- C Messages
- D Operational Limits
- E Using ASAP
- Index
Online Database Synchronization
HP NonStop RDF System Management Manual—524388-003
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Updater Phase 2
Phase 2
Phase 2 completes when the extractor is certain the synch-complete image record has
been successfully written in all image trails, and the extractor’s restart location is at a
point in the audit trail following the TMP control point record associated with the
completion of phase 1, part 3, above.
Upon completion of phase 2, the extractor logs message 782.
Updater Phase 2
You cannot start the updaters until the extractor has completed phase 2.
Phase 2 completes when the updater encounters the synch-complete image record in
the image trail. At that time the updater has processed all audit information that might
have been generated during the load or backup operation, and synchronization is
complete for the associated database volume.
Upon completion of phase 2, the updater logs message 782.
Extractor Restart Considerations During
Online Database Synchronization
A number of circumstances can cause the extractor to restart during online database
synchronization, such as a primary CPU failure affecting either the extractor or receiver
process. Whenever the extractor encounters a restart condition it automatically
recovers and resumes its synchronization functions. Where it resumes, however,
depends upon where it was when the restart condition occurred.
•
If the restart condition occurs prior to the start of phase 1, the extractor resumes
wherever the receiver tells it to.
•
If the restart condition occurs after phase 1 has begun, the extractor may choose to
resume at an earlier position than the receiver tells it to. It does this to ensure that
it has handled all committed and aborted transactions correctly. If the extractor
does resume at an earlier position, it logs message 775. Additionally, regardless of
whether or not it adjusted the restart position, the extractor may log messages 766,
767, and 768 again, even if it had logged any of them prior to the restart condition.
Note. If you are replicating only the master audit trail (MAT), you may start the updaters as
soon as the extractor issues its 782 event message. If you are also replicating one or more
auxiliary audit trails, however, you must also wait for all of the auxiliary extractors to report 0:00
RTD times before starting the updaters.